Miscible Blends Comprising Copolyesters of Aromatic Dicarboxylic Acid With CHDM and Either NPG or TMCD

ABSTRACT

This invention relates to a miscible blend comprising: 
     (1) A first copolyester comprising terephthalic acid residues, isophthalic acid residues, or mixtures thereof and diol residues comprising 1 to 100 mole % 1,4-cyclohexanedimethanol residues and 0 to 99 mole % of at least one modifying glycol chosen from 2,2-dimethyl-1,3-propanediol, and ethylene glycol residues; and
 
(2) a second copolyester comprising terephthalic acid residues, isophthalic acid residues, or mixtures thereof and diol residues comprising 1,4-cyclohexanedimethanol residues and 2,2,4,4-tetramethyl-1,3-cyclobutanediol residues,

FIELD OF THE INVENTION

The present invention relates to polymer blends comprising at least one copolyester of aromatic dicarboxylic acid(s) (phthalic acid(s)) with 2,2,4,4-tetramethyl-1,3-cyclobutanediol (TMCD) and at least one copolyester of aromatic dicarboxylic acid(s) (phthalic acid(s)) with 1,4 cyclohexanedimethanol (CHDM) and 2,2-dimethyl-1,3-propanediol or neopentyl glycol (NPG).

BACKGROUND OF THE INVENTION

Polymer based thermoplastic compositions; either as homopolymers, copolymers, or blends of polymers, that are transparent (clear), have good physical properties such as dimensional stability, high heat resistance, and good impact strength are useful for many applications. For example, the polycarbonate of 4,4′-isopropylidenediphenol (bisphenol A polycarbonate) is a well known engineering molding and film/sheet forming plastic. Bisphenol A polycarbonate is a well known engineering molding plastic. Bisphenol A polycarbonate is a clear, high-performance plastic having good physical properties such as dimensional stability, high heat resistance, and good impact strength. Although bisphenol-A polycarbonate has many good physical properties, its relatively high melt viscosity leads to poor melt processability and the polycarbonate exhibits poor chemical resistance. Hence other polymer systems are desirable.

Blends of polymers display different physical properties based upon the nature of the polymers blended together as well as the concentration of each polymer in the blend. Attempts have been made to blend bisphenol-A polycarbonate with other polymers that have good chemical resistance, processability, and machinability. These attempts to improve melt processability, chemical resistance and other physical properties of bisphenol-A polycarbonate have been made by blending bisphenol A polycarbonate with polymers such as polystyrene, elastomers, polyesters, and polyesterimides. However, blends of bisphenol-A polycarbonate with other polymeric materials usually have resulted in immiscible blend compositions. Immiscible blend compositions are inadequate for many uses because they are not clear.

Clear, miscible blends of any two polymers are rare. The term “miscible” refers to blends that are a mixture on a molecular level wherein intimate polymer-polymer interaction is achieved. Miscible blends are clear, not translucent or opaque. In addition, differential scanning calorimetry testing detects only a single glass transition temperature (Tg) for miscible blends composed of two or more components.

Thus, there is a need in the art for a polymer blend that is useful in molding plastics, fibers, and films and which also have excellent clarity, chemical resistance, good heat resistance and good toughness.

SUMMARY OF THE INVENTION

It is believed that certain polymer blends comprising at least one copolyester of aromatic dicarboxylic acid(s) (phthalic acid(s)) with 2,2,4,4-tetramethyl-1,3-cyclobutanediol (TMCD) and at least one copolyester of aromatic dicarboxylic acid(s) (phthalic acid(s)) with 1,4 cyclohexanedimethanol (CHDM) and 2,2-dimethyl-1,3-propanediol or neopentyl glycol (NPG) have excellent clarity, chemical resistance, good heat resistance and good toughness.

This invention relates to a miscible blend comprising:

(1) 1 to 99 percent by weight of a first copolyester comprising:

-   -   (a) diacid residues comprising about 65 to 100 mole percent of         dicarboxylic acid residues selected from the group consisting of         terephthalic acid residues, isophthalic acid residues, or         mixtures thereof; about 0 to 35 mole percent of modifying diacid         residues having from about 2 to 20 carbon atoms, wherein the         total mole percent of diacid residues is equal to 100 mole         percent; and     -   (b) diol residues comprising about 1 to 100 mole percent         1,4-cyclohexanedimethanol residues, and about 99 to 0 mole         percent diol residues selected from the group consisting of         2,2-dimethyl-1,3-propanediol, ethylene glycol and         1,4-cyclohexanedimethanol; and about 0 to 10 mole percent of         other modifying glycol residues having about 3 to 16 carbon         atoms, wherein the total mole percent of diol residues is equal         to 100 mole percent; and

(2) 1 to 99 percent by weight of a second copolyester comprising:

-   -   (a) diacid residues comprising about 65 to 100 mole percent of         dicarboxylic acid residues selected from the group consisting of         terephthalic acid residues, isophthalic acid residues, or         mixtures thereof; and about 0 to 35 mole percent of modifying         diacid residues having from about 2 to 20 carbon atoms, wherein         the total mole percent of diacid residues is equal to 100 mole         percent; and,     -   (b) diol residues comprising about 1 to 99 mole percent         1,4-cyclohexanedimethanol residues and about 99 to 1 mole         percent 2,2,4,4-tetramethyl-1,3-cyclobutanediol residues,         wherein the total mole percent of diol residues is equal to 100         mole percent;

wherein the total weight percent for the blend equals 100 weight percent.

In one aspect, the polyester blends are useful in articles of manufacture including, but not limited to, extruded, calendered, and/or molded articles including, but not limited to, injection molded articles, extrusion articles, cast extrusion articles, profile extrusion articles, melt spun articles, thermoformed articles, extrusion molded articles, injection blow molded articles, injection stretch blow molded articles, extrusion blow molded articles and extrusion stretch blow molded articles. These articles can include, but are not limited to, films, bottles, containers, sheet and/or fibers.

In one aspect, the polyester blends useful in the invention may be used in various types of film and/or sheet, including but not limited to extruded film(s) and/or sheet(s), calendered film(s) and/or sheet(s), compression molded film(s) and/or sheet(s), solution casted film(s) and/or sheet(s). Methods of making film and/or sheet include but are not limited to extrusion, calendering, compression molding, and solution casting.

DETAILED DESCRIPTION OF THE INVENTION

Certain blends of certain copolyester of phthalic acids such as terephthalic acid (TPA) and isophthalic acid (IPA) with TMCD and CHDM with other copolyesters exhibit at least one improved property, and preferably, at least two improved properties in combination such as clarity and miscibility as well as heat deflection temperature, notched and unnotched Izod impact strength, flexural modulus, flexural strength and tensile strength. The polymer blends provided by the present invention contain at least two or more copolyesters that comprise:

-   -   (1) diacid residues comprising 65 to 100, preferably 70 to 100,         more preferably 75 to 100, more preferably 85 to 100, and most         preferably 95 to 100 mole percent of TPA, IPA or mixtures         thereof and the like; and 0 to about 35 mole percent of         modifying diacid residues having from about 2 to 20 carbon         atoms, wherein the total mole percent of diacid residues is         equal to 100 mole percent; and;     -   (2) diol residues comprising about 1 to 99, preferably 5 to 95,         more preferably 15 to 95, even more preferably 15 to 85, and         most preferably 20 to 80 mole percent CHDM residues; and about         95 to 5, preferably 95 to 15, more preferably 85 to 15, and most         preferably 80 to 20 mole percent diol residues selected from the         group; EG, TMCD, NPG and the like; and about 0 to 10 mole         percent of other modifying glycol residues having about 3 to 16         carbon atoms, wherein the total mole percent of diol residues is         equal to 100 mole percent;         wherein the total weight percent for the blend composition         comprising at least two or more copolyesters is equal to 100         weight percent.

Also, the polymer blends provided by the present invention contain at least two or more copolyesters that comprise:

-   -   (1) diacid residues of TPA, IPA or mixtures thereof with         preferred molar percent TPA:IPA ratios of about 100:0, 95:5,         83:17, 74:26, 65:35 and the like; and 0 to about 35 mole percent         of modifying diacid residues having from about 2 to 20 carbon         atoms, wherein the total mole percent of diacid residues is         equal to 100 mole percent; and;     -   (2) diol residues of NPG, CHDM or mixtures thereof with         preferred molar percent NPG:CHDM ratios of about 0:100, 5:95,         10:90, 20:80, 30:70, 40:60, 50:50, 60:40, 70:30, 75:25, 80:20,         and the like; and about 0 to 10 mole percent of other modifying         glycol residues having about 3 to 16 carbon atoms, wherein the         total mole percent of diol residues is equal to 100 mole         percent;         wherein the total weight percent for the blend composition         comprising at least two or more copolyesters is equal to 100         weight percent.

Furthermore, blends of at least one or more copolyesters provided by the present invention comprise:

Another embodiment of the present invention relates to a polymer blend comprising:

-   -   (1) A first copolyester (copolyester 1) of about 0.1 to 80,         preferably 0.1 to 70, more preferably 0.1 to 60, even more         preferably 0.1 to 50, percent by weight comprising:         -   (a) diacid residues comprising 65 to 100, preferably 70 to             100, more preferably 75 to 100, more preferably 85 to 100,             and most preferably 95 to 100 mole percent of TPA, IPA or             mixtures thereof and the like; and about 0 to 35 mole             percent of modifying diacid residues having from about 2 to             20 carbon atoms, wherein the total mole percent of diacid             residues is equal to 100 mole percent; and,         -   (b) diol residues comprising about 99 to 1, preferably 5 to             95, more preferably 15 to 95, even more preferably 15 to 85,             and most preferably 20 to 80 mole percent CHDM residues and             about 95 to 5, preferably 95 to 15, more preferably 85 to             15, and most preferably 80 to 20 mole percent diol residues             selected from the group; EG, NPG and the like; and about 0             to 10 mole percent of other modifying glycol residues having             about 3 to 16 carbon atoms,             wherein the total mole percent of diol residues is equal to             100 mole percent; and,     -   (2) A second copolyester (copolyester 2) of about 20 to 99.9,         preferably 30 to 99.9, more preferably 40 to 99.9, even more         preferably 50 to 99.9, percent by weight comprising:         -   (a) diacid residues comprising about 65 to 100, preferably             70 to 100, more preferably 75 to 100, more preferably 85 to             100, and most preferably 95 to 100 mole percent of TPA, IPA             or mixtures thereof and the like; and 0 to about 35 mole             percent of modifying diacid residues having from about 2 to             20 carbon atoms, wherein the total mole percent of diacid             residues is equal to 100 mole percent; and,         -   (b) diol residues comprising about 1 to 99, preferably 5 to             95, more preferably 15 to 95, even more preferably 15 to 85,             and most preferably 20 to 80 mole percent TMCD residues, and             the like; and about 0 to 10 mole percent of other modifying             glycol residues having about 3 to 16 carbon atoms, wherein             the total mole percent of diol residues is equal to 100 mole             percent;     -    wherein the total weight percent for the blend composition         comprising copolyesters (1) and (2) is equal to 100 weight         percent.

Another embodiment of the present invention relates to a polymer blend comprising:

-   -   (1) A first copolyester (copolyester 1) of about 50 to 0.1,         preferably 40 to 0.1, more preferably 30 to 0.1, even more         preferably 20 to 0.1, percent by weight comprising:         -   (a) diacid residues comprising 65 to 100, preferably 70 to             100, more preferably 75 to 100, more preferably 85 to 100,             and most preferably 95 to 100 mole percent of TPA, IPA or             mixtures thereof and the like; and about 0 to 35 mole             percent of modifying diacid residues having from about 2 to             20 carbon atoms, wherein the total mole percent of diacid             residues is equal to 100 mole percent; and,         -   (b) diol residues comprising about 99 to 1, preferably 5 to             95, more preferably 15 to 95, even more preferably 15 to 85,             and most preferably 20 to 80 mole percent CHDM residues and             about 95 to 5, preferably 95 to 15, more preferably 85 to             15, and most preferably 80 to 20 mole percent diol residues             selected from the group; EG, NPG and the like; and about 0             to 10 mole percent of other modifying glycol residues having             about 3 to 16 carbon atoms,     -   wherein the total mole percent of diol residues is equal to 100         mole percent; and,     -   (2) A second copolyester (copolyester 2) of about 99.9 to 50,         preferably 99.9 to 60, more preferably 99.9 to 70, even more         preferably 99.9 to 80, percent by weight comprising:         -   (a) diacid residues comprising about 65 to 100, preferably             70 to 100, more preferably 75 to 100, more preferably 85 to             100, and most preferably 95 to 100 mole percent of TPA, IPA             or mixtures thereof and the like; and 0 to about 35 mole             percent of modifying diacid residues having from about 2 to             20 carbon atoms, wherein the total mole percent of diacid             residues is equal to 100 mole percent; and,         -   (b) diol residues comprising about 1 to 99, preferably 5 to             95, more preferably 15 to 95, even more preferably 15 to 85,             and most preferably 20 to 80 mole percent TMCD residues, and             the like; and about 0 to 10 mole percent of other modifying             glycol residues having about 3 to 16 carbon atoms, wherein             the total mole percent of diol residues is equal to 100 mole             percent;     -    wherein the total weight percent for the blend composition         comprising copolyesters (1) and (2) is equal to 100 weight         percent.

An embodiment of the present invention is a miscible blend comprising copolyester 1 wherein the diol portion of the copolyester conforms to one of the following combinations as shown:

about 1 to 80 mole percent NPG and about 20 to 99 mole percent CHDM

about 5 to 80 mole percent NPG and about 20 to 95 mole percent CHDM

about 15 to 80 mole percent NPG and about 20 to 85 mole percent CHDM

about 20 to 80 mole percent NPG and about 20 to 80 mole percent CHDM

about 30 to 80 mole percent NPG and about 20 to 70 mole percent CHDM

about 40 to 80 mole percent NPG and about 20 to 60 mole percent CHDM

about 50 to 80 mole percent NPG and about 20 to 50 mole percent CHDM

about 55 to 80 mole percent NPG and about 20 to 45 mole percent CHDM

about 60 to 80 mole percent NPG and about 20 to 40 mole percent CHDM

about 65 to 80 mole percent NPG and about 20 to 35 mole percent CHDM

about 70 to 80 mole percent NPG and about 20 to 30 mole percent CHDM

about 75 to 80 mole percent NPG and about 20 to 25 mole percent CHDM

about 77 to 80 mole percent NPG and about 20 to 23 mole percent CHDM

wherein the total mole percent of diol residues is equal to 100 mole percent

An embodiment of the present invention is a miscible blend comprising copolyester 2 wherein the diol portion of the copolyester conforms to one of the following combinations as shown:

about 5 to 95 mole percent CHDM and about 95 to 5 mole percent TMCD

about 15 to 85 mole percent CHDM and about 85 to 15 mole percent TMCD

about 20 to 80 mole percent CHDM and about 80 to 20 mole percent TMCD

about 45 to 90 mole percent CHDM and about 55 to 10 mole percent TMCD

about 50 to 85 mole percent CHDM and about 50 to 15 mole percent TMCD

about 55 to 85 mole percent CHDM and about 45 to 15 mole percent TMCD

about 55 to 80 mole percent CHDM and about 45 to 20 mole percent TMCD

about 65 to 80 mole percent CHDM and about 35 to 20 mole percent TMCD

wherein the total mole percent of diol residues is equal to 100 mole percent.

Still another embodiment of the present invention are blends as described above where the blend contains chain extenders or the blend components, copolyester (1), (2), or both (1) and (2) are either branched or contain either chain extenders prior to or during blend formation.

And yet further, an embodiment of the present invention are blends as described above where the blend or at least one or more of the two or more copolyesters (1) and (2) further comprise a third component including additives, branching agents, acidic phosphorus-containing compounds, or up to 35% of another copolyester and mixtures thereof; wherein the total weight percent for the blend composition comprising copolyesters (1) and (2) is equal to 100 weight percent.

The invention also includes molded or formed articles, film, sheet, and/or fibers comprising the polymer blends of the invention which may be formed by any conventional method known in the art as well as a process for making such articles, film, sheet, and/or fibers comprising the steps of injection molding, extrusion blow molding, film/sheet extruding or calendering the polymer blend(s).

In one aspect, the at least two or more copolyesters (1) and (2) that are useful in the invention contain ethylene glycol residues.

In one aspect, the at least two or more copolyesters (1) and (2) that are useful in the invention contain no ethylene glycol residues.

In one aspect, the polyester blends of the invention are useful in articles of manufacture including, but not limited to, extruded, calendered, and/or molded articles including, but not limited to, injection molded articles, extruded articles, cast extrusion articles, profile extrusion articles, melt spun articles, thermoformed articles, extrusion molded articles, injection blow molded articles, injection stretch blow molded articles, extrusion blow molded articles and extrusion stretch blow molded articles. These articles can include, but are not limited to, films, bottles, containers, sheet and/or fibers.

In one aspect, the polyester blends of the invention may be used in various types of film and/or sheet, including but not limited to extruded film(s) and/or sheet(s), calendered film(s) and/or sheet(s), compression molded film(s) and/or sheet(s), solution casted film(s) and/or sheet(s). Methods of making film and/or sheet include but are not limited to extrusion, calendering, compression molding, and solution casting.

DETAILED DESCRIPTION OF THE INVENTION

This invention encompasses polymer blends involving copolyesters of phthalic acid with TMCD and CHDM and copolyesters which comprise CHDM and NPG.

Surprisingly, the present invention provides polymer blends exhibit an improved combination of at least two properties such as clarity and miscibility as well as heat deflection temperatures, notched and unnoticed Izod impact strength, flexural modulus, flexural strength and tensile strength.

Unless otherwise indicated, all numbers expressing quantities of ingredients, properties such as molecular weight, reaction conditions, and so forth used in the specification and claims are to be understood as being modified in all instances by the term “about.” Accordingly, unless indicated to the contrary, the numerical parameters set forth in the following specification and attached claims are approximations that may vary depending upon the desired properties sought to be obtained by the present invention. At the very least, each numerical parameter should at least be construed in light of the number of reported significant digits and by applying ordinary rounding techniques. Further, the ranges stated in this disclosure and the claims are intended to include the entire range specifically and not just the endpoint(s). For example, a range stated to be 0 to 10 is intended to disclose all whole numbers between 0 and 10 such as, for example 1, 2, 3, 4, etc., all fractional numbers between 0 and 10, for example 1.5, 2.3, 4.57, 6.1113, etc., and the endpoints 0 and 10. Also, a range associated with chemical substituant groups such as, for example, “C₁ to C₅ hydrocarbons”, is intended to specifically include and disclose C₁ and C₅ hydrocarbons as well as C₂, C₃, and C₄ hydrocarbons.

Notwithstanding that the numerical ranges and parameters setting forth the broad scope of the invention are approximations, the numerical values set forth in the specific examples are reported as precisely as possible. Any numerical value, however, inherently contains certain errors necessarily resulting from the standard deviation found in their respective testing measurements.

The term “polyester”, as used herein, is intended to include “copolyesters” and is understood to mean a synthetic polymer prepared by the polycondensation of one or more difunctional carboxylic acids with one or more difunctional hydroxyl compounds. Typically the difunctional carboxylic acid is a dicarboxylic acid and the difunctional hydroxyl compound is a dihydric alcohol such as, for example, glycols and diols. The term “residue”, as used herein, means any organic structure incorporated into a polymer or plasticizer through a polycondensation reaction involving the corresponding monomer. The term “repeating unit”, as used herein, means an organic structure having a dicarboxylic acid residue and a diol residue bonded through a carbonyloxy group. Thus, the dicarboxylic acid residues may be derived from a dicarboxylic acid monomer or its associated acid halides, esters, salts, anhydrides, or mixtures thereof. As used herein, therefore, the term dicarboxylic acid is intended to include dicarboxylic acids and any derivative of a dicarboxylic acid, including its associated acid halides, esters, half-esters, salts, half-salts, anhydrides, mixed anhydrides, or mixtures thereof, useful in a polycondensation process with a diol to make high molecular weight polyester.

The polymer blends of present invention include at least two or more polyester(s) comprising dicarboxylic acid residues, diol residues, and, optionally, branching monomer residues. The polyester(s) included in the present invention contain substantially equal molar proportions of acid residues (100 mole %) and diol residues (100 mole %) which react in substantially equal proportions such that the total moles of repeating units is equal to 100 mole %. The mole percentages provided in the present disclosure, therefore, may be based on the total moles of acid residues, the total moles of diol residues, or the total moles of repeating units. For example, a polyester containing 20 mole % isophthalic acid, based on the total acid residues, means the polyester contains 20 mole % isophthalic acid residues out of a total of 100 mole % acid residues. Thus, there are 20 moles of isophthalic acid residues among every 100 moles of acid residues. In another example, a polyester containing 30 mole % ethylene glycol, based on the total diol residues, means the polyester contains 30 mole % ethylene glycol residues out of a total of 100 mole % diol residues. Thus, there are 30 moles of ethylene glycol residues among every 100 moles of diol residues.

The polymer blends of the invention comprise at least two or more copolyester(s); one copolyester comprising phthalic acid(s), NPG and CHDM, and another copolyester comprising phthalic acid(s) with TMCD and CHDM that are miscible and typically exhibit a single glass transition temperature (abbreviated herein as “Tg”) as a blend, as measured by well-known techniques such as, for example, differential scanning calorimetry (“DSC”). The desired crystallization kinetics from the melt also may be achieved by the addition of polymeric additives such as, for example, plasticizers, or by altering the molecular weight characteristics of the polymer. The polyesters utilized in the present invention are amorphous or semi-crystalline and have glass transition temperatures of about 40 to 140° C., copolyester(s). Copolyesters of phthalic acid(s), NPG and CHDM (copolyester 1) have glass transition temperatures that are preferably about 60 to 100° C., whereas copolyesters of phthalic acid(s), TMCD and CHDM have glass transition temperatures that are preferably about 90 to 120° C. The polyesters typically have an inherent viscosity (I.V.) of about 0.3 to 1.2 dL/g, preferably about 0.6 to 1.1 dL/g. As used herein, I.V. refers to inherent viscosity determinations made at 25° C. using 0.50 gram of polymer per 100 mL of a solvent composed of 60 weight percent phenol and 40 weight percent tetrachloroethane. The basic method of determining the I.V. of the polyesters herein is set forth in ASTM method D2857-95.

For embodiments of the invention, the copolyesters useful in the polymer blends of the invention may exhibit at least one of the following inherent viscosities as determined in 60/40 (wt/wt) phenol/tetrachloroethane at a concentration of 0.25 g/50 ml at 25° C.: 0.45 to 1.2 dL/g; 0.45 to 1.1 dL/g; 0.45 to 1 dL/g; 0.45 to 0.98 dL/g; 0.45 to 0.95 dL/g; 0.45 to 0.90 dL/g; 0.45 to 0.85 dL/g; 0.45 to 0.80 dL/g; 0.45 to 0.75 dL/g; 0.45 to less than 0.75 dL/g; 0.45 to 0.72 dL/g; 0.45 to 0.70 dL/g; 0.45 to less than 0.70 dL/g; 0.45 to 0.68 dL/g; 0.45 to less than 0.68 dL/g; 0.45 to 0.65 dL/g; 0.50 to 1.2 dL/g; 0.50 to 1.1 dL/g; 0.50 to 1 dL/g; 0.50 to less than 1 dL/g; 0.50 to 0.98 dL/g; 0.50 to 0.95 dL/g; 0.50 to 0.90 dL/g; 0.50 to 0.85 dL/g; 0.50 to 0.80 dL/g; 0.50 to 0.75 dL/g; 0.50 to less than 0.75 dL/g; 0.50 to 0.72 dL/g; 0.50 to 0.70 dL/g; 0.50 to less than 0.70 dL/g; 0.50 to 0.68 dL/g; 0.50 to less than 0.68 dL/g; 0.50 to 0.65 dL/g; 0.55 to 1.2 dL/g; 0.55 to 1.1 dL/g; 0.55 to 1 dL/g; 0.55 to less than 1 dL/g; 0.55 to 0.98 dL/g; 0.55 to 0.95 dL/g; 0.55 to 0.90 dL/g; 0.55 to 0.85 dL/g; 0.55 to 0.80 dL/g; 0.55 to 0.75 dL/g; 0.55 to less than 0.75 dL/g; 0.55 to 0.72 dL/g; 0.55 to 0.70 dL/g; 0.55 to less than 0.70 dL/g; 0.55 to 0.68 dL/g; 0.55 to less than 0.68 dL/g; 0.55 to 0.67 dL/g; 0.55 to 0.65 dL/g; 0.58 to 1.2 dL/g; 0.58 to 1.1 dL/g; 0.58 to 1 dL/g; 0.58 to less than 1 dL/g; 0.58 to 0.98 dL/g; 0.58 to 0.95 dL/g; 0.58 to 0.90 dL/g; 0.58 to 0.85 dL/g; 0.58 to 0.80 dL/g; 0.58 to 0.75 dL/g; 0.58 to less than 0.75 dL/g; 0.58 to 0.72 dL/g; 0.58 to 0.70 dL/g; 0.58 to less than 0.70 dL/g; 0.58 to 0.68 dL/g; 0.58 to less than 0.68 dL/g; 0.58 to 0.65 dL/g; 0.60 to 1.2 dL/g; 0.60 to 1.1 dL/g; 0.60 to 1 dL/g; 0.60 to less than 1 dL/g; 0.60 to 0.98 dL/g; 0.60 to 0.95 dL/g; 0.60 to 0.90 dL/g; 0.60 to 0.85 dL/g; 0.60 to 0.80 dL/g; 0.60 to 0.75 dL/g; 0.60 to less than 0.75 dL/g; 0.60 to 0.72 dL/g; 0.60 to 0.70 dL/g; 0.60 to less than 0.70 dL/g; 0.60 to 0.68 dL/g; 0.60 to less than 0.68 dL/g; 0.60 to 0.65 dL/g; 0.60 to 0.64 dL/g; 0.61 to 0.68 dL/g; 0.64 to 0.65 dL/g; 0.65 to 1.2 dL/g; 0.65 to 1.1 dL/g; 0.65 to 1 dL/g; 0.65 to less than 1 dL/g; 0.65 to 0.98 dL/g; 0.65 to 0.95 dL/g; 0.65 to 0.90 dL/g; 0.65 to 0.85 dL/g; 0.65 to 0.80 dL/g; 0.65 to 0.75 dL/g; 0.65 to less than 0.75 dL/g; 0.65 to 0.72 dL/g; 0.65 to 0.70 dL/g; 0.65 to less than 0.70 dL/g; 0.68 to 1.2 dL/g; 0.68 to 1.1 dL/g; 0.68 to 1 dL/g; 0.68 to less than 1 dL/g; 0.68 to 0.98 dL/g; 0.68 to 0.95 dL/g; 0.68 to 0.90 dL/g; 0.68 to 0.85 dL/g; 0.68 to 0.80 dL/g; 0.68 to 0.75 dL/g; 0.68 to less than 0.75 dL/g; 0.68 to 0.72 dL/g; 0.69 to 0.75 dL/g; 0.76 dL/g to 1.2 dL/g; 0.76 dL/g to 1.1 dL/g; 0.76 dL/g to 1 dL/g; 0.76 dL/g to less than 1 dL/g; 0.76 dL/g to 0.98 dL/g; 0.76 dL/g to 0.95 dL/g; 0.76 dL/g to 0.90 dL/g 0.80 dL/g to 1.2 dL/g; 0.80 dL/g to 1.1 dL/g; 0.80 dL/g to 1 dL/g; 0.80 dL/g to less than 1 dL/g; 0.80 dL/g to 1.2 dL/g; 0.80 dL/g to 0.98 dL/g; 0.80 dL/g to 0.95 dL/g; 0.80 dL/g to 0.90 dL/g.

The diacids useful in the present invention may comprise from about 65 to 100 mole percent, preferably 80 to 100 mole percent, more preferably, 85 to 100 mole percent, even more preferably, 90 to 100 mole percent, and further 95 to 100 mole percent, of dicarboxylic acids selected from the group consisting of terephthalic acid residues, isophthalic acids, or mixtures thereof. For example, the polyester may comprise about 70 to about 100 mole % of diacid residues from terephthalic acid and 0 to about 30 mole % diacid residues from isophthalic acid (in one embodiment, about 0.1 to 30 mole percent isophthalic acid.

Copolyesters of the polymer blends of the invention also may further comprise from about 0 to about 30 mole percent, preferably 0 to 10 mole percent, and more preferably, 0.1 to 10 mole percent of the residues of one or more modifying diacids containing about 2 to about 20 carbon atoms (not terephthalic acid and/or isophthalic acid). Examples of modifying diacids containing about 2 to about 20 carbon atoms that may be used include but are not limited to aliphatic dicarboxylic acids, alicyclic dicarboxylic acids, aromatic dicarboxylc acids, or mixtures of two or more of these acids. Specific examples of modifying dicarboxylic acids include, but are not limited to, one or more of succinic acid, glutaric acid, adipic acid, suberic acid, sebacic acid, azelaic acid, dimer acid, sulfoisophthalic acid. Additional examples of modifying diacids are fumaric, maleic, itaconic, 1,3-cyclohexanedicarboxylic, diglycolic, 2,5-norbornanedicarboxyclic, phthalic acid, diphenic, 4,4′-oxydibenzoic, and 4,4′-sulfonyldibenzoic. Other examples of modifying dicarboxylic acid residues include but are not limited to naphthalenedicarboxylic acid and 1,4-cyclohexanedicarboxylic acid. Any of the various isomers of naphthalenedicarboxylic acid or mixtures of isomers may be used, but the 1,4-, 1,5-, 2,6-, and 2,7-isomers are preferred. Cycloaliphatic dicarboxylic acids such as, for example, 1,4-cyclohexanedicarboxylic acid may be present at the pure cis or trans isomer or as a mixture of cis and trans isomers.

For the copolyesters of the present invention, the molar ratio of cis/trans 2,2,4,4-tetramethyl-1,3-cyclobutanediol can vary from the pure form of each and mixtures thereof. In certain embodiments, the molar percentages for cis and/or trans 2,2,4,4,-tetramethyl-1,3-cyclobutanediol are greater than 50 mole % cis and less than 50 mole % trans; or greater than 55 mole % cis and less than 45 mole % trans; or 30 to 70 mole % cis and 70 to 30 mole % trans; or 40 to 60 mole % cis and 60 to 40 mole % trans; or 50 to 70 mole % trans and 50 to 30 mole % cis; or 50 to 70 mole % cis and 50 to 30 mole % trans; or 60 to 70 mole % cis and 30 to 40 mole % trans; or greater than 70 mole % cis and less than 30 mole % trans; wherein the total mole percentages for cis- and trans-2,2,4,4-tetramethyl-1,3-cyclobutanediol is equal to 100 mole %. In an additional embodiment, the molar ratio of cis/trans 2,2,4,4-tetramethyl-1,3-cyclobutanediol can vary within the range of 50/50 to 0/100, for example, between 40/60 to 20/80.

The cyclohexanedimethanol may be cis, trans, or a mixture thereof, for example, a cis/trans ratio of 60:40 to 40:60 or a cis/trans ratio of 70:30 to 30:70. In another embodiment, the trans-cyclohexanedimethanol can be present in an amount of 60 to 80 mole % and the cis-cyclohexanedimethanol can be present in an amount of 20 to 40 mole % wherein the total percentages of cis-cyclohexanedimethanol and trans-cyclohexanedimethanol is equal to 100 mole %. In particular embodiments, the trans-cyclohexanedimethanol can be present in an amount of 60 mole % and the cis-cyclohexanedimethanol can be present in an amount of 40 mole %. In particular embodiments, the trans-cyclohexanedimethanol can be present in an amount of 70 mole % and the cis-cyclohexanedimethanol can be present in an amount of 30 mole %. Any of 1,1-, 1,2-, 1,3-, 1,4-isomers of cyclohexanedimethanol or mixtures thereof may be present in the glycol component of this invention.

The copolyesters also comprises diol residues that may comprise about 20 to about 80 mole percent of the residues of CHDM, 20 to about 80 mol % NPG (copolyester 1) or TMCD (copolyester 2), and 0 to 10 mole percent of one or more modifying diol residues containing 2 to about 20 carbon atoms. As used herein, the term “diol” is synonymous with the term “glycol” and means any dihydric alcohol. For example, in copolyester (1), the diol residues may comprise about: (a) 45 to 95 mole percent, or about 50 to 80 mole percent, or about 55 to 75 mole percent, or about 55 to 70 mole percent, and about 58 to 68 mole percent of the residues of CHDM, based on the total mole percentage of diol residues equaling 100 mole percent, (b) 55 to 5 mole percent, or about 50 to 20 mole percent, or about 45 to 30 mole percent, or about 42 to 32 mole percent of the residues of neopentyl glycol, based on the total mole percentage of diol residues equaling 100 mole percent, and (c) about 0 to 30 mole percent, or about 0 to 10 mole percent, or about 0 to 5 mole percent, or 0.1 to 10 mole percent, and or about 0.1 to about 5 mole percent of the residues of one or more modifying diols for copolyesters which are selected from one or more of ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, diethylene glycol, 1,6-hexanediol, 1,8-octanediol, 2,2,4-trimethyl-1,3-pentanediol, 1,3-cyclohexanedimethanol, or polyalkylene glycol. Further examples of modifying diols that may be used in the polyesters of our invention are triethylene glycol; polyethylene glycols; 2,4-dimethyl-2-ethylhexane-1,3-diol; 2,2-dimethyl-1,3-propanediol; 2-ethyl-2-butyl-1,3-propanediol; 2-ethyl-2-isobutyl-1,3-propanediol; 1,3-butanediol; thiodiethanol; 1,2-cyclohexanedimethanol; p-xylylenediol; bisphenol S; or combinations of one or more of any of these modifying glycols. The cycloaliphatic diols, for example, 1,3- and 1,4-CHDM, may be present as their pure cis or trans isomers or as a mixture of cis and trans isomers. In another example, the diol residues may comprise from about 45 to about 95 mole percent of the residues of CHDM, about 55 to 5 mole percent of the residues of neopentyl glycol, and from about 0 to 10 mole percent of the residues of ethylene glycol. In a further example, the diol residues may comprise from about 50 to about 80 mole percent of the residues of CHDM, from about 50 to about 20 mole percent of the residues of neopentyl glycol, and from about 0 to about 10 mole percent of the residues of ethylene glycol. In another example, the diol residues may comprise from about 55 to 70 mole percent of the residues of CHDM, from about 45 to 30 mole percent of the residues of neopentyl glycol, and about 0 to 10 mole percent of the residues of modifying diol residues, preferably, 0.1 to 10 mole percent of the residues of modifying diol residues, for example, ethylene glycol. In yet another example, the diol residues may comprise from about 58 to about 68 mole percent of the residues of CHDM, and from about 42 to about 32 mole percent of the residues of neopentyl glycol.

In connection with any of the described ranges for mole percentages of the diol residues present herein, any of the described mole percentages of the diacid residues. may be used In general. In combination with the preferred ranges for the mole percentages of the diol residues stated herein, it is another embodiment of the invention that the diacid residues of copolyesters comprise about 80 to about 100 mole percent of the residues of terephthalic acid. While modifying diols are contemplated within the scope of this invention, residues of CHDM and NPG are also envisioned within the scope of this invention as the only diol residues comprised in copolyesters. In a preferred embodiment, CHDM and neopentyl glycol are the only diol residues present in copolyesters, and the diacid residues comprise about 80 to about 100 mole percent of the residues of terephthalic acid.

The diacid and diol residues of one of the embodiments of the polyesters included in the polymer blends of the invention consist essentially of:

(1) diacid residues comprising at least 70 mole percent, preferably about 80 to 100 mole percent, of terephthalic acid residues and 0 to about 30 mole percent isophthalic acid residues; and (2) diol residues comprising about 40 to 99 mole percent, preferably about 50 to 80 mole percent, CHDM residues and about 0.1 to 60 mole percent, preferably about 20 to 50 mole percent, neopentyl glycol residues.

The polymer blends of the invention typically comprise from about 1 to 99 weight percent, or 0.1 to 75 weight percent, or 0.1 to 50 weight percent, or 10 to 30 weight percent, or 15 to 30 weight percent, of at least one copolyester of phthalic acid with TMCD and CHDM (2) comprising: (1) a diol component comprising about 20 to 40 mol percent TMCD residues; and (2) about 0 to 10 mole percent modifying diol residues having 2 to 16 carbon atoms; wherein the total mole percent of the diol residues is equal to 100 mole percent; and comprise from about 99 to 1 weight percent, or 99.9 to 25 weight percent, or 99.9 to 50 weight percent, or 75 to 50 weight percent of at least one or more additional copolyester (1), wherein the total weight percent of copolyester of phthalic acid with TMCD and CHDM (2) and copolyesters (1) is equal to 100 weight percent.

The copolyesters in the present invention comprise from about 0 to about 10 or 0.01 to about 10 weight percent (wt %), or from about 0.05 to about 5 weight percent, or from about 0.01 to 1 weight percent, or 0.1 to 0.7 weight percent, based on the total weight of the polyester, of one or more residues of a branching monomer having 3 or more carboxyl substituents, hydroxyl substituents, or a combination thereof. Examples of branching monomers include, but are not limited to, multifunctional acids or glycols such as trimellitic acid, trimellitic anhydride, pyromellitic dianhydride, trimethylolpropane, glycerol, pentaerythritol, citric acid, tartaric acid, 3-hydroxyglutaric acid and the like. In one embodiment, the branching monomer residues comprise about 0.1 to about 0.7 mole percent of one or more residues of: trimellitic anhydride, pyromellitic dianhydride, glycerol, sorbitol, 1,2,6-hexanetriol, pentaerythritol, trimethylolethane, or trimesic acid. The branching monomer may be added to the polyester reaction mixture or blended with the polyester in the form of a concentrate as described, for example, in U.S. Pat. Nos. 5,654,347 and 5,696,176.

The CHDM residues typically have a trans isomer content in the range of about 60 to 100%. However, a preferred isomer content is in the range of about 60 to about 80% trans isomer.

The polyesters are readily prepared by conventional methods well known in the art. For example, melt phase or a combination of melt phase and solid phase polycondensation techniques may be used if desired. The diacid residues of the polyesters may be derived from the dicarboxylic acid or a derivative of the diacid such as the lower alkyl esters, e.g., dimethyl terepthalate, acid halides, e.g., diacid chlorides, or, in some cases, anhydrides.

The polyesters present in the instant invention are readily prepared from the appropriate dicarboxylic acids, esters, anhydrides, or salts, the appropriate diol or diol mixtures, and optionally branching monomers using typical poly-condensation reaction conditions. They may be made by continuous, semi-continuous, and batch modes of operation and may utilize a variety of reactor types. Examples of suitable reactor types include, but are not limited to, stirred tank, continuous stirred tank, slurry, tubular, wiped-film, falling film, or extrusion reactors. The term “continuous” as used herein means a process wherein reactants are introduced and products withdrawn simultaneously in an uninterrupted manner. By “continuous” it is meant that the process is substantially or completely continuous in operation in contrast to a “batch” process. “Continuous” is not meant in any way to prohibit normal interruptions in the continuity of the process due to, for example, start-up, reactor maintenance, or scheduled shut down periods. The term “batch” process as used herein means a process wherein all the reactants are added to the reactor and then processed according to a predetermined course of reaction during which no material is fed or removed into the reactor. The term “semicontinuous” means a process where some of the reactants are charged at the beginning of the process and the remaining reactants are fed continuously as the reaction progresses. Alternatively, a semicontinuous process may also include a process similar to a batch process in which all the reactants are added at the beginning of the process except that one or more of the products are removed continuously as the reaction progresses.

The polyesters included in the present invention are prepared by procedures known to persons skilled in the art. The reaction of the diol, dicarboxylic acid, and optional branching monomer components may be carried out using conventional polyester polymerization conditions. For example, when preparing the polyester by means of an ester interchange reaction, i.e., from the ester form of the dicarboxylic acid components, the reaction process may comprise two steps. In the first step, the diol component and the dicarboxylic acid component, such as, for example, dimethyl terephthalate, are reacted at elevated temperatures, typically, about 150° C. to about 250° C. for about 0.5 to about 8 hours at pressures ranging from about 0.0 kPa gauge to about 414 kPa gauge (60 pounds per square inch, “psig”). Preferably, the temperature for the ester interchange reaction ranges from about 180° C. to about 230° C. for about 1 to about 4 hours while the preferred pressure ranges from about 103 kPa gauge (15 psig) to about 276 kPa gauge (40 psig). Thereafter, the reaction product is heated under higher temperatures and under reduced pressure to form the polyester with the elimination of diol, which is readily volatilized under these conditions and removed from the system. This second step, or polycondensation step, is continued under higher vacuum and a temperature which generally ranges from about 230° C. to about 350° C., preferably about 250° C. to about 310° C. and, most preferably, about 260° C. to about 290° C. for about 0.1 to about 6 hours, or preferably, for about 0.2 to about 2 hours, until a polymer having the desired degree of polymerization, as determined by inherent viscosity, is obtained. The polycondensation step may be conducted under reduced pressure which ranges from about 53 kPa (400 torr) to about 0.013 kPa (0.1 torr). Stirring or appropriate conditions are used in both stages to ensure adequate heat transfer and surface renewal of the reaction mixture. The reaction rates of both stages are increased by appropriate catalysts such as, for example, alkoxy titanium compounds, alkali metal hydroxides and alcoholates, salts of organic carboxylic acids, alkyl tin compounds, metal oxides, and the like. A three-stage manufacturing procedure, similar to that described in U.S. Pat. No. 5,290,631, may also be used, particularly when a mixed monomer feed of acids and esters is employed.

To ensure that the reaction of the diol component and dicarboxylic acid component by an ester interchange reaction is driven to completion, it is sometimes desirable to employ about 1.05 to about 2.5 moles of diol component to one mole dicarboxylic acid component. Persons of skill in the art will understand, however, that the ratio of diol component to dicarboxylic acid component is generally determined by the design of the reactor in which the reaction process occurs.

In the preparation of polyester by direct esterification, i.e., from the acid form of the dicarboxylic acid component, polyesters are produced by reacting the dicarboxylic acid or a mixture of dicarboxylic acids with the diol component or a mixture of diol components and the branching monomer component. The reaction is conducted at a pressure of from about 7 kPa gauge (1 psig) to about 1379 kPa gauge (200 psig), preferably less than 689 kPa (100 psig) to produce a low molecular weight polyester product having an average degree of polymerization of from about 1.4 to about 10. The temperatures employed during the direct esterification reaction typically range from about 180° C. to about 280° C., more preferably ranging from about 220° C. to about 270° C. This low molecular weight polymer may then be polymerized by a polycondensation reaction. Examples of the catalyst materials that may be used in the synthesis of the polyesters utilized in the present invention may include but are not limited to tin, titanium, manganese, zinc, cobalt, antimony, gallium, lithium, calcium, silicon and germanium. Such catalyst systems are described in U.S. Pat. Nos. 3,907,754, 3,962,189, 4,010,145, 4,356,299, 5,017,680, 5,668,243 and 5,681,918, herein incorporated by reference in their entirety. The amount of catalytic metal used may range from about 5 to 100 ppm but the use of catalyst concentrations of about 5 to about 35 ppm titanium is preferred in order to provide polyesters having good color, thermal stability and electrical properties. Phosphorus compounds frequently are used in combination with the catalyst metals and any of the phosphorus compounds normally used in making polyesters may be used. Up to about 100 ppm phosphorus typically may be used.

The at least two or more copolyesters (1) and (2) that are useful in the polymer blends of the invention can comprise at least one chain extender. Suitable chain extenders include, but are not limited to, multifunctional (including, but not limited to, bifunctional) isocyanates, multifunctional epoxides, including for example, epoxylated novolacs, and phenoxy resins. In certain embodiments, chain extenders may be added at the end of the polymerization process or after the polymerization process. If added after the polymerization process, chain extenders can be incorporated by compounding or by addition during conversion processes such as injection molding or extrusion. The amount of chain extender used can vary depending on the specific monomer composition used and the physical properties desired but is generally about 0.1 percent by weight to about 10 percent by weight, such as about 0.1 to about 5 percent by weight, based on the total weight of the polyester.

The glass transition temperature (Tg) of the at least two or more copolyesters (1) and (2) that are useful in the polymer blends of the invention was determined using a TA DSC 2920 from Thermal Analyst Instrument at a scan rate of 20° C./min.

In one embodiment, certain copolyesters (1) and (2) as well as the polymer blends useful in this invention can be visually clear. The term “visually clear” is defined herein as an appreciable absence of cloudiness, haziness, and/or muddiness, when inspected visually. In another embodiment, when the polyesters are blended with polycarbonate, including but not limited to, bisphenol A polycarbonates, the blends can be visually clear.

Notched Izod impact strength, as described in ASTM D256, is a common method of measuring toughness.

When tin is added to the polyesters useful in the blends of the invention, it is added to the process of making the polyester in the form of a tin compound. The amount of the tin compound added to the polyesters useful in the blends of the invention can be measured in the form of tin atoms present in the final polyester blend, for example, by weight measured in ppm.

When phosphorus is added to the polyesters useful in the blends of the invention, it is added to the process of making the polyester in the form of a phosphorus compound. In one embodiment, this phosphorus compound can comprise at least one phosphate ester(s). The amount of phosphorus compound, [for example, phosphate ester(s)] added to the polyesters useful in the blends of the invention can be measured in the form of phosphorus atoms present in the final polyester blend, for example, by weight measured in ppm.

In one aspect, the phosphorus compounds useful in copolyesters (1) and (2) useful in the polymer blends of the invention comprise phosphoric acid, phosphorous acid, phosphonic acid, phosphinic acid, phosphonous acid, and various esters and salts thereof. The esters can be alkyl, branched alkyl, substituted alkyl, difunctional alkyl, alkyl ethers, aryl, and substituted aryl.

In one aspect, the phosphorus compounds useful in copolyesters (1) and (2) useful in the polymer blends of the invention can be chosen from at least one of substituted or unsubstituted alkyl phosphate esters, substituted or unsubstituted aryl phosphate esters, substituted or unsubstituted mixed alkyl aryl phosphate esters, diphosphites, salts of phosphoric acid, phosphine oxides, and mixed alkyl aryl phosphites, reaction products thereof, and mixtures thereof. The phosphate esters include esters in which in which the phosphoric acid is fully esterified or only partially esterified.

In one embodiment, the phosphate esters useful in copolyesters (1) and (2) and/or the aliphatic polyesters useful in the polymer blends of the invention include but are not limited to dibutylphenyl phosphate, triphenyl phosphate, tricresyl phosphate, tributyl phosphate, tri-2-ethylhexyl phosphate, trioctyl phosphate, and/or mixtures thereof, including particularly mixtures of tributyl phosphate and tricresyl phosphate, and mixtures of isocetyl diphenyl phosphate and 2-ethylhexyl diphenyl phosphate.

In one embodiment, the phosphate esters useful in copolyesters (1) and (2) and/or the aliphatic polyesters useful in the polymer blends of the invention include but are not limited to, at least one of the following: trialkyl phosphates, triaryl phosphates, alkyl diaryl phosphates, and mixed alkyl aryl phosphates.

In one embodiment, the phosphate esters useful in copolyesters (1) and (2) useful in the polymer blends of the invention include but are not limited to, at least one of the following: triaryl phosphates and mixed alkyl aryl phosphates.

When phosphorus is added to the polyesters and/or polyester blends and/or process of making the polyesters useful in the invention, it is added in the form of a phosphorus compound, for example, at least one phosphate ester(s). The amount of phosphorus compound(s), (for example, at least one phosphate ester), is added to the at least two or more copolyesters (1) and (2) that are useful in the invention and/or polyester blends of the invention and/or processes of the invention can be measured in the form of phosphorus atoms present in the final polyester, for example, by weight measured in ppm.

The invention further relates to a polymer blend comprising polyesters other than the copolyesters (1) and (2) as useful previously in the polymer blends of the invention. The blend comprises:

from 5 to 95 weight % of at least one of the copolyester (1) described herein; and

from 5 to 95 weight % of at least one of the copolyester (2) described herein; and,

from 0 to 95 weight % of at least one additional polymeric components not including the polyesters of (a) and (b);

wherein the total weight percent of all polymeric components in the polymer blends of the invention equals a total of 100 weight %.

Suitable examples of the additional polymeric components include, but are not limited to, nylon; polyesters different than those described herein; polyamides such as ZYTEL® from DuPont; polystyrene; polystyrene copolymers; styrene acrylonitrile copolymers; acrylonitrile butadiene styrene copolymers; poly(methylmethacrylate); acrylic copolymers; poly(ether-imides) such as ULTEM® (a poly(ether-imide) from General Electric); polyphenylene oxides such as poly(2,6-dimethylphenylene oxide) or poly(phenylene oxide)/polystyrene blends such as NORYL 1000® (a blend of poly(2,6-dimethylphenylene oxide) and polystyrene resins from General Electric); polyphenylene sulfides; polyphenylene sulfide/sulfones; poly(ester-carbonates); polycarbonates such as LEXAN® (a polycarbonate from General Electric); polysulfones; polysulfone ethers; and poly(ether-ketones) of aromatic dihydroxy compounds; or mixtures of any of the foregoing polymers.

All polymer blends (also intended to encompass the word “mixtures”) of the invention can be prepared by conventional processing techniques known in the art, such as melt blending or solution blending. The compositions of this invention are prepared by any conventional mixing methods. For example, in one embodiment, the blending method comprises mixing the aliphatic-aromatic and aliphatic polyester in powder or granular form in an extruder and extruding the mixture into strands, chopping the strands into pellets and molding the pellets into the desired article.

In addition, the polyester blends of the invention may also contain from 0.01 to 25% by weight of the overall composition common additives such as colorants, dyes, mold release agents, flame retardants, plasticizers, nucleating agents, stabilizers, including but not limited to, UV stabilizers, thermal stabilizers and/or reaction products thereof, fillers, and impact modifiers. Examples of typical commercially available impact modifiers well known in the art and useful in this invention include, but are not limited to, ethylene/propylene terpolymers, functionalized polyolefins such as those containing methyl acrylate and/or glycidyl methacrylate, styrene-based block copolymeric impact modifiers, and various acrylic core/shell type impact modifiers. Residues of such additives are also contemplated as part of the polyester composition

Reinforcing materials may be useful in the polymer blends of this invention. The reinforcing materials may include, but are not limited to, carbon filaments, silicates, mica, clay, talc, titanium dioxide, Wollastonite, glass flakes, glass beads and fibers, and polymeric fibers and combinations thereof. In one embodiment, the reinforcing materials include glass, such as, fibrous glass filaments, mixtures of glass and talc, glass and mica, and glass and polymeric fibers.

The polyester blends of the invention may also comprise at least one tin compound. When tin is added to the at least two or more copolyesters (1) and (2) that are useful in the invention and/or process of making the polyesters useful in the invention, it is added to the process of making the polyester in the form of a tin compound. The amount of the tin compound added to the polyesters useful in the invention and/or processes of making the polyesters useful in the invention can be measured in the form of tin atoms present in the final AAPE polyester and/or final aliphatic polyester and/or the final polymer blend, for example, by weight measured in ppm.

The polyester portion of the polyester blends useful in the invention can be made by processes known from the literature such as, for example, by processes in homogenous solution, by transesterification processes in the melt, and by two phase interfacial processes. Suitable methods include, but are not limited to, the steps of reacting one or more dicarboxylic acids with one or more glycols at a temperature of 100□ C to 315□ C at a pressure of 0.1 to 760 mm Hg for a time sufficient to form polyester. See U.S. Pat. No. 3,772,405 for methods of producing polyesters, the disclosure regarding such methods is hereby incorporated herein by reference.

In other aspects of the invention, the Tg of certain copolyesters useful in the polyester blends of the invention can be at least one of the following ranges: 60 to 200° C.; 60 to 190° C.; 60 to 180° C.; 60 to 170° C.; 60 to 160° C.; 60 to 155° C.; 60 to 150° C.; 60 to 145° C.; 60 to 140° C.; 60 to 138° C.; 60 to 135° C.; 60 to 130° C.; 60 to 125° C.; 60 to 120° C.; 60 to 115° C.; 60 to 110° C.; 60 to 105° C.; 60 to 100° C.; 60 to 95° C.; 60 to 90° C.; 60 to 85° C.; 60 to 80° C.; 60 to 75° C.; 65 to 200° C.; 65 to 190° C.; 65 to 180° C.; 65 to 170° C.; 65 to 160° C.; 65 to 155° C.; 65 to 150° C.; 65 to 145° C.; 65 to 140° C.; 65 to 138° C.; 65 to 135° C.; 65 to 130° C.; 65 to 125° C.; 65 to 120° C.; 65 to 115° C.; 65 to 110° C.; 65 to 105° C.; 65 to 100° C.; 65 to 95° C.; 65 to 90° C.; 65 to 85° C.; 65 to 80° C.; 65 to 75° C.; 70 to 200° C.; 70 to 190° C.; 70 to 180° C.; 70 to 170° C.; 70 to 160° C.; 70 to 155° C.; 70 to 150° C.; 70 to 145° C.; 70 to 140° C.; 70 to 138° C.; 70 to 135° C.; 70 to 130° C.; 70 to 125° C.; 70 to 120° C.; 70 to 115° C.; 70 to 110° C.; 70 to 105° C.; 70 to 100° C.; 70 to 95° C.; 70 to 90° C.; 70 to 85° C.; 70 to 80° C.; 70 to 75° C.; 75 to 200° C.; 75 to 190° C.; 75 to 180° C.; 75 to 170° C.; 75 to 160° C.; 75 to 155° C.; 75 to 150° C.; 75 to 145° C.; 75 to 140° C.; 75 to 138° C.; 75 to 135° C.; 75 to 130° C.; 75 to 125° C.; 75 to 120° C.; 75 to 115° C.; 75 to 110° C.; 75 to 105° C.; 75 to 100° C.; 75 to 95° C.; 75 to 90° C.; 75 to 85° C.; 75 to 80° C.; 80 to 200° C.; 80 to 190° C.; 80 to 180° C.; 80 to 170° C.; 80 to 160° C.; 80 to 155° C.; 80 to 150° C.; 80 to 145° C.; 80 to 140° C.; 80 to 138° C.; 80 to 135° C.; 80 to 130° C.; 80 to 125° C.; 80 to 120° C.; 80 to 115° C.; 80 to 110° C.; 80 to 105° C.; 80 to 100° C.; 80 to 95° C.; 80 to 90° C.; 80 to 85° C.; 85 to 200° C.; 85 to 190° C.; 85 to 180° C.; 85 to 170° C.; 85 to 160° C.; 85 to 155° C.; 85 to 150° C.; 85 to 145° C.; 85 to 140° C.; 85 to 138° C.; 85 to 135° C.; 85 to 130° C.; 85 to 125° C.; 85 to 120° C.; 85 to 115° C.; 85 to 110° C.; 85 to 105° C.; 85 to 100° C.; 85 to 95° C.; 85 to 90° C.; 90 to 200° C.; 90 to 190° C.; 90 to 180° C.; 90 to 170° C.; 90 to 160° C.; 90 to 155° C.; 90 to 150° C.; 90 to 145° C.; 90 to 140° C.; 90 to 138° C.; 90 to 135° C.; 90 to 130° C.; 90 to 125° C.; 90 to 120° C.; 90 to 115° C.; 90 to 110° C.; 90 to 105° C.; 90 to 100° C.; 90 to 95° C.; 95 to 200° C.; 95 to 190° C.; 95 to 180° C.; 95 to 170° C.; 95 to 160° C.; 95 to 155° C.; 95 to 150° C.; 95 to 145° C.; 95 to 140° C.; 95 to 138° C.; 95 to 135° C.; 95 to 130° C.; 95 to 125° C.; 95 to 120° C.; 95 to 115° C.; 95 to 110° C.; 95 to 105° C.; 95 to 100° C.; 100 to 200° C.; 100 to 190° C.; 100 to 180° C.; 100 to 170° C.; 100 to 160° C.; 100 to 155° C.; 100 to 150° C.; 100 to 145° C.; 100 to 140° C.; 100 to 138° C.; 100 to 135° C.; 100 to 130° C.; 100 to 125° C.; 100 to 120° C.; 100 to 115° C.; 100 to 110° C.; 105 to 200° C.; 105 to 190° C.; 105 to 180° C.; 105 to 170° C.; 105 to 160° C.; 105 to 155° C.; 105 to 150° C.; 105 to 145° C.; 105 to 140° C.; 105 to 138° C.; 105 to 135° C.; 105 to 130° C.; 105 to 125° C.; 105 to 120° C.; 105 to 115° C.; 105 to 110° C.; 110 to 200° C.; 110 to 190° C.; 110 to 180° C.; 110 to 170° C.; 110 to 160° C.; 110 to 155° C.; 110 to 150° C.; 110 to 145° C.; 110 to 140° C.; 110 to 138° C.; 110 to 135° C.; 110 to 130° C.; 110 to 125° C.; 110 to 120° C.; 110 to 115° C.; 115 to 200° C.; 115 to 190° C.; 115 to 180° C.; 115 to 170° C.; 115 to 160° C.; 115 to 155° C.; 115 to 150° C.; 115 to 145° C.; 115 to 140° C.; 115 to 138° C.; 115 to 135° C.; 110 to 130° C.; 115 to 125° C.; 115 to 120° C.; 120 to 200° C.; 120 to 190° C.; 120 to 180° C.; 120 to 170° C.; 120 to 160° C.; 120 to 155° C.; 120 to 150° C.; 120 to 145° C.; 120 to 140° C.; 120 to 138° C.; 120 to 135° C.; 120 to 130° C.; 125 to 200° C.; 125 to 190° C.; 125 to 180° C.; 125 to 170° C.; 125 to 165° C.; 125 to 160° C.; 125 to 155° C.; 125 to 150° C.; 125 to 145° C.; 125 to 140° C.; 125 to 138° C.; 125 to 135° C.; 127 to 200° C.; 127 to 190° C.; 127 to 180° C.; 127 to 170° C.; 127 to 160° C.; 127 to 150° C.; 127 to 145° C.; 127 to 140° C.; 127 to 138° C.; 127 to 135° C.; 130 to 200° C.; 130 to 190° C.; 130 to 180° C.; 130 to 170° C.; 130 to 160° C.; 130 to 155° C.; 130 to 150° C.; 130 to 145° C.; 130 to 140° C.; 130 to 138° C.; 130 to 135° C.; 135 to 200° C.; 135 to 190° C.; 135 to 180° C.; 135 to 170° C.; 135 to 160° C.; 135 to 155° C.; 135 to 150° C.; 135 to 145° C.; 135 to 140° C.; 140 to 200° C.; 140 to 190° C.; 140 to 180° C.; 140 to 170° C.; 140 to 160° C.; 140 to 155° C.; 140 to 150° C.; 140 to 145° C.; 148 to 200° C.; 148 to 190° C.; 148 to 180° C.; 148 to 170° C.; 148 to 160° C.; 148 to 155° C.; 148 to 150° C.; greater than 148 to 200° C.; greater than 148 to 190° C.; greater than 148 to 180° C.; greater than 148 to 170° C.; greater than 148 to 160° C.; greater than 148 to 155° C.; 150 to 200° C.; 150 to 190° C.; 150 to 180° C.; 150 to 170° C.; 150 to 160; 155 to 190° C.; 155 to 180° C.; 155 to 170° C.; and 155 to 165° C.

In other aspects of the invention, the Tg of certain copolyesters (1) and (2) useful in the polyester compositions of the invention can be at least one of the following ranges: 90 to 120° C.; 95 to 120° C.; 100 to 120° C.; 105 to 120° C.; 110 to 120° C.; 90 to 115° C.; 95 to 115° C.; 100-115° C.; 105 to 115° C.; 90 to 110° C.; 95 to 110° C.; 100 to 110° C.; 90 to 100° C.; 90 to 105° C.; 95 to 105° C.; and 90 to 100° C.

In other aspects of the invention, the glycol component for the copolyester (2) useful in blends of the invention include but are not limited to at least one of the following combinations of ranges: 5 to 99 mole % TMCD and 1 to 95 mole % CHDM; 5 to 95 mole % TMCD and 5 to 95 mole % CHDM; 5 to 90 mole TMCD and 10 to 95 mole % CHDM; 5 to 85 mole % TMCD and 15 to 95 mole CHDM; 5 to 80 mole % TMCD and 20 to 95 mole % CHDM, 5 to 75 mole % TMCD and 25 to 95 mole % CHDM; 5 to 70 mole % TMCD and 30 to 95 mole % CHDM; 5 to 65 mole % TMCD and 35 to 95 mole % CHDM; 5 to 60 mole % TMCD and 40 to 95 mole % CHDM; 5 to 55 mole % TMCD and 45 to 95 mole % CHDM; and 5 to 50 mole % TMCD and 50 to 95 mole % CHDM.

In other aspects of the invention, the glycol component for the copolyester (2) useful in the polymer blends of the invention include but are not limited to at least one of the following combinations of ranges: 5 to less than 50 mole % TMCD and greater than 50 to 95 mole % CHDM; 5 to 45 mole % TMCD and 55 to 95 mole % CHDM; 5 to 40 mole % TMCD and 60 to 95 mole % CHDM; 5 to 35 mole % TMCD and 65 to 95 mole % CHDM; 5 to less than 35 mole % TMCD and greater than 65 to 95 mole % CHDM; 5 to 30 mole % TMCD and 70 to 95 mole % CHDM; 5 to 25 mole % TMCD and 75 to 95 mole % CHDM; 5 to 20 mole % TMCD and 80 to 95 mole % CHDM; 5 to 15 mole % TMCD and 85 to 95 mole % CHDM; 5 to 10 mole % TMCD and 90 to 95 mole % CHDM; greater than 5 to less than 10 mole % TMCD and less than 90 to greater than 95 mole % CHDM; 5.5 mole % to 9.5 mole % TMCD and 94.5 mole % to 90.5 mole % CHDM; and 6 to 9 mole % TMCD and 94 to 91 mole % CHDM.

In other aspects of the invention, the glycol component for the copolyesters (1) and (2) useful in the polymer blends of the invention include but are not limited to at least one of the following combinations of ranges: 10 to 99 mole % TMCD and 1 to 90 mole % CHDM; 10 to 95 mole % TMCD and 5 to 90 mole % CHDM; 10 to 90 mole % TMCD and 10 to 90 mole % CHDM; 10 to 85 mole % TMCD and 15 to 90 mole % CHDM; 10 to 80 mole % TMCD and 20 to 90 mole % CHDM; 10 to 75 mole % TMCD and 25 to 90 mole % CHDM; 10 to 70 mole % TMCD and 30 to 90 mole % CHDM; 10 to 65 mole % TMCD and 35 to 90 mole % CHDM; 10 to 60 mole % TMCD and 40 to 90 mole % CHDM; 10 to 55 mole % TMCD and 45 to 90 mole % CHDM; 10 to 50 mole % TMCD and 50 to 90 mole % CHDM; 10 to less than 50 mole % TMCD and greater than 50 to 90 mole % CHDM; 10 to 45 mole % TMCD and 55 to 90 mole % CHDM; 10 to 40 mole % TMCD and 60 to 90 mole % CHDM; 10 to 35 mole % TMCD and 65 to 90 mole % CHDM; 10 to less than 35 mole % TMCD and greater than 65 to 90% CHDM; 10 to 30 mole % TMCD and 70 to 90 mole % CHDM; 10 to 25 mole % TMCD and 75 to 90 mole % CHDM; 10 to 20 mole % TMCD and 80 to 90 mole % CHDM; and 10 to 15 mole % TMCD and 85 to 90 mole % CHDM.

In other aspects of the invention, the glycol component for the copolyester (2) useful in the polymer blends of the invention include but are not limited to at least one of the following combinations of ranges: 15 to 99 mole % TMCD and 1 to 85 mole % CHDM; 15 to 95 mole % TMCD and 5 to 85 mole % CHDM; 15 to 90 mole % TMCD and 10 to 85 mole % CHDM; 15 to 85 mole % TMCD and 15 to 85 mole % CHDM; 15 to 80 mole % TMCD and 20 to 85 mole % CHDM; 15 to 75 mole % TMCD and 25 to 85 mole % CHDM; 15 to 70 mole % TMCD and 30 to 85 mole % CHDM; 15 to 65 mole % TMCD and 35 to 85 mole % CHDM; 15 to 60 mole % TMCD and 40 to 85 mole % CHDM; 15 to 55 mole % TMCD and 45 to 85 mole % CHDM; 15 to 50 mole % TMCD and 50 to 85 mole % CHDM; 15 to less than 50 mole % TMCD and greater than 50 to 85 mole % CHDM; 15 to 45 mole % TMCD and 55 to 85 mole % CHDM; 15 to 40 mole % TMCD and 60 to 85 mole % CHDM; 15 to 35 mole % TMCD and 65 to 85 mole % CHDM; 15 to 30 mole % TMCD and 70 to 85 mole % CHDM; 15 to 25 mole % TMCD and 75 to 85 mole % CHDM; and 15 to 24 mole % TMCD and 76 to 85 mole % CHDM.

In other aspects of the invention, the glycol component for the copolyester (2) useful in the polymer blends of the invention include but are not limited to at least one of the following combinations of ranges: 20 to 99 mole % TMCD and 1 to 80 mole % CHDM; 20 to 95 mole % TMCD and 5 to 80 mole % CHDM; 20 to 90 mole % TMCD and 10 to 80 mole % CHDM; 20 to 85 mole % TMCD and 15 to 80 mole % CHDM; 20 to 80 mole % TMCD and 20 to 80 mole % CHDM; 20 to 75 mole % TMCD and 25 to 80 mole % CHDM; 20 to 70 mole % TMCD and 30 to 80 mole % CHDM; 20 to 65 mole % TMCD and 35 to 80 mole % CHDM; 20 to 60 mole % TMCD and 40 to 80 mole % CHDM; 20 to 55 mole % TMCD and 45 to 80 mole % CHDM; 20 to 50 mole % TMCD and 50 to 80 mole % CHDM; 20 to less than 50 mole % TMCD and greater than 50 to 80 mole % CHDM; 20 to 45 mole % TMCD and 55 to 80 mole % CHDM; 20 to 40 mole % TMCD and 60 to 80 mole % CHDM; 20 to 35 mole % TMCD and 65 to 80 mole % CHDM; 20 to 30 mole % TMCD and 70 to 80 mole % CHDM; and 20 to 25 mole % TMCD and 75 to 80 mole % CHDM.

In other aspects of the invention, the glycol component for the copolyester and (2) useful in the polymer blends of the invention include but are not limited to at least one of the following combinations of ranges: 25 to 99 mole % TMCD and 1 to 75 mole % CHDM; 25 to 95 mole % TMCD and 5 to 75 mole % CHDM; 25 to 90 mole % TMCD and 10 to 75 mole % CHDM; 25 to 85 mole % TMCD and 15 to 75 mole % CHDM; 25 to 80 mole % TMCD and 20 to 75 mole % CHDM; 25 to 75 mole % TMCD and 25 to 75 mole % CHDM; 25 to 70 mole % TMCD and 30 to 75 mole % CHDM; 25 to 65 mole % TMCD and 35 to 75 mole % CHDM; 25 to 60 mole % TMCD and 40 to 75 mole % CHDM; 25 to 55 mole % TMCD and 45 to 75 mole % CHDM; 25 to 50 mole % TMCD and 50 to 75 mole % CHDM; 25 to less than 50 mole % TMCD and greater than 50 to 75 mole % CHDM; 25 to 45 mole % TMCD and 55 to 75 mole % CHDM; 25 to 40 mole % TMCD and 60 to 75 mole % CHDM; 25 to 35 mole % TMCD and 65 to 75 mole % CHDM; and 25 to 30 mole % TMCD and 70 to 75 mole % CHDM.

In other aspects of the invention, the glycol component for the copolyester (2) useful in the blends of the invention include but are not limited to at least one of the following combinations of ranges: 30 to 99 mole % TMCD and 1 to 70 mole % CHDM; 30 to 95 mole % TMCD and 5 to 70 mole % CHDM; 30 to 90 mole % TMCD and 10 to 70 mole % CHDM; 30 to 85 mole % TMCD and 15 to 70 mole % CHDM; 30 to 80 mole % TMCD and 20 to 70 mole % CHDM; 30 to 75 mole % TMCD and 25 to 70 mole % CHDM; 30 to 70 mole % TMCD and 30 to 70 mole % CHDM; 30 to 65 mole % TMCD and 35 to 70 mole % CHDM; 30 to 60 mole % TMCD and 40 to 70 mole % CHDM; 30 to 55 mole % TMCD and 45 to 70 mole % CHDM; 30 to 50 mole % TMCD and 50 to 70 mole % CHDM; 30 to less than 50 mole % TMCD and greater than 50 to 70 mole % CHDM; 30 to 45 mole % TMCD and 55 to 70 mole % CHDM; 30 to 40 mole % TMCD and 60 to 70 mole % CHDM; 30 to 35 mole % TMCD and 65 to 70 mole % CHDM; 31 to 35 mole % TMCD and 65 to 69 mole % CHDM.

In other aspects of the invention, the glycol component for the copolyesters (2) useful in the blends of the invention include but are not limited to at least one of the following combinations of ranges: 35 to 99 mole % TMCD and 1 to 65 mole % CHDM; 35 to 95 mole % TMCD and 5 to 65 mole % CHDM; 35 to 90 mole % TMCD and 10 to 65 mole % CHDM; 35 to 85 mole % TMCD and 15 to 65 mole % CHDM; 35 to 80 mole % TMCD and 20 to 65 mole % CHDM; 35 to 75 mole % TMCD and 25 to 65 mole % CHDM; 35 to 70 mole % TMCD and 30 to 65 mole % CHDM; 35 to 65 mole % TMCD and 35 to 65 mole % CHDM; 35 to 60 mole % TMCD and 40 to 65 mole % CHDM; 35 to 55 mole % TMCD and 45 to 65 mole % CHDM; 35 to 50 mole % TMCD and 50 to 65 mole % CHDM; 35 to less than 50 mole % TMCD and greater than 50 to 65 mole % CHDM; 35 to 45 mole % TMCD and 55 to 65 mole % CHDM; 35 to 40 mole % TMCD and 60 to 65 mole % CHDM.

In other aspects of the invention, the glycol component for the copolyester (2) useful in the blends of the invention include but are not limited to at least one of the following combinations of ranges: 40.1 to 100 mole % TMCD and 1 to 59.9 mole % CHDM 40 to 99 mole % TMCD and 1 to 60 mole % CHDM; 40 to 95 mole % TMCD and 5 to 60 mole % CHDM; 40 to 90 mole % TMCD and 10 to 60 mole % CHDM; 40 to 85 mole % TMCD and 15 to 60 mole % CHDM; 40 to 80 mole % TMCD and 20 to 60 mole % CHDM; 40 to 75 mole % TMCD and 25 to 60 mole % CHDM; 40 to 70 mole % TMCD and 30 to 60 mole % CHDM; 40 to 65 mole % TMCD and 35 to 60 mole % CHDM; 40 to 60 mole % TMCD and 40 to 60 mole % CHDM; 40 to 55 mole % TMCD and 45 to 60 mole % CHDM; 40 to less than 50 mole % TMCD and greater than 50 to 60 mole % CHDM; 40 to 50 mole % TMCD and 50 to 60 mole % CHDM; and 40 to 45 mole % TMCD and 55 to 60 mole % CHDM.

In other aspects of the invention, the glycol component for the copolyesters (2) useful in the blends of the invention include but are not limited to at least one of the following combinations of ranges: 45 to 100 mole % TMCD and 0 to 55 mole % CHDM; 45 to 99 mole % TMCD and 1 to 55 mole % CHDM; 45 to 95 mole % TMCD and 5 to 55 mole % CHDM; 45 to 90 mole % TMCD and 10 to 55 mole % CHDM; 45 to 85 mole % TMCD and 15 to 55 mole % CHDM; 45 to 80 mole % TMCD and 20 to 55 mole % CHDM; 45 to 75 mole % TMCD and 25 to 55 mole % CHDM; 45 to 70 mole % TMCD and 30 to 55 mole % CHDM; 45 to 65 mole % TMCD and 35 to 55 mole % CHDM; 45 to 60 mole % TMCD and 40 to 55 mole % CHDM; greater than 45 to 55 mole % TMCD and 45 to less than 55 mole % CHDM; 45 to 55 mole % TMCD and 45 to 55 mole % CHDM; and 45 to 50 mole % TMCD and 50 to 60 mole % CHDM.

In other aspects of the invention, the glycol component for the copolyesters (2) useful in the polymer blends of the invention include but are not limited to at least one of the following combinations of ranges: 55 to 99 mole % TMCD and 1 to 45 mole % CHDM; 55 to 95 mole % TMCD and 5 to 45 mole % CHDM; 55 to 90 mole % TMCD and 10 to 45 mole % CHDM; 55 to 85 mole % TMCD and 15 to 45 mole % CHDM; 55 to 80 mole % TMCD and 20 to 45 mole % CHDM; 55 to 75 mole % TMCD and 25 to 45 mole % CHDM; 55 to 70 mole % TMCD and 30 to 45 mole % CHDM; 55 to 65 mole % TMCD and 35 to 45 mole % CHDM; and 55 to 60 mole % TMCD and 40 to 45 mole % CHDM.

In other aspects of the invention, the glycol component for the copolyesters (2) useful in the polymer blends of the invention include but are not limited to at least one of the following combinations of ranges: 60 to 99 mole % TMCD and 1 to 40 mole % CHDM; 60 to 95 mole % TMCD and 5 to 40 mole % CHDM; 60 to 90 mole % TMCD and 10 to 40 mole % CHDM; 60 to 85 mole % TMCD and 15 to 40 mole % CHDM; 60 to 80 mole % TMCD and 20 to 40 mole % CHDM; 60 to 75 mole % TMCD and 25 to 40 mole % CHDM; and 60 to 70 mole % TMCD and 30 to 40 mole % CHDM.

In other aspects of the invention, the glycol component for the polyesters useful in the polymer blends of the invention include but are not limited to at least one of the following combinations of ranges: 65 to 99 mole % TMCD and 1 to 35 mole % CHDM; 65 to 95 mole % TMCD and 5 to 35 mole % CHDM; 65 to 90 mole % TMCD and 10 to 35 mole % CHDM; 65 to 85 mole % TMCD and 15 to 35 mole % CHDM; 65 to 80 mole % TMCD and 20 to 35 mole % CHDM; 65 to 75 mole % TMCD and 25 to 35 mole % CHDM; and 65 to 70 mole % TMCD and 30 to 35 mole % CHDM.

In other aspects of the invention, the glycol component for the polyesters useful in the polymer blends of the invention include but are not limited to at least one of the following combinations of ranges: 70 to 99 mole % TMCD and 1 to 30 mole % CHDM; 70 to 95 mole % TMCD and 5 to 30 mole % CHDM; 70 to 90 mole % TMCD and 10 to 30 mole % CHDM; 70 to 85 mole % TMCD and 15 to 30 mole % CHDM; 70 to 80 mole % TMCD and 20 to 30 mole % CHDM; 70 to 75 mole % TMCD and 25 to 30 mole % CHDM.

In other aspects of the invention, the glycol component for the copolyesters (2) useful in the polymer blends of the invention include but are not limited to at least one of the following combinations of ranges: 75 to 99 mole % TMCD and 1 to 25 mole % CHDM; 75 to 95 mole % TMCD and 5 to 25 mole % CHDM; 75 to 90 mole % TMCD and 10 to 25 mole % CHDM; and 75 to 85 mole % TMCD and 15 to 25 mole % CHDM.

In other aspects of the invention, the glycol component for the copolyesters (2) useful in the invention include but are not limited to at least one of the following combinations of ranges: 20 to 40 mole % TMCD, 20 to 40 mole % CHDM and 30 to 60 mole % ethylene glycol; 20 to 35 mole % TMCD, 20 to 40 mole % CHDM and 30 to 60 mole % ethylene glycol; 20 to 30 mole % TMCD, 20 to 40 mole % CHDM and 30 to 60 mole % ethylene glycol; and 20 to 25 mole % TMCD, 20 to 40 mole % CHDM and 30 to 60 mole % ethylene glycol.

In other aspects of the invention, the glycol component for the copolyesters (2) useful in the invention include but are not limited to at least one of the following combinations of ranges: 25 to 40 mole % TMCD, 20 to 40 mole % CHDM and 30 to 55 mole % ethylene glycol; 25 to 35 mole % TMCD, 120 to 40 mole % CHDM and 30 to 55 mole % ethylene glycol; and 25 to 30 mole % TMCD, 20 to 40 mole % CHDM and 30 to 55 mole % ethylene glycol.

In other aspects of the invention, the glycol component for the copolyesters (2) useful in the invention include but are not limited to at least one of the following combinations of ranges: 30 to 40 mole % TMCD, 20 to 40 mole % CHDM and 30 to 50 mole % ethylene glycol; 30 to 35 mole % TMCD, 20 to 40 mole % CHDM and 30 to 50 mole % ethylene glycol.

In other aspects of the invention, the glycol component for the copolyesters (2) useful in the invention include but are not limited to at least one of the following combinations of ranges: 20 to 40 mole % TMCD, 20 to 35 mole % CHDM and 30 to 60 mole % ethylene glycol; 20 to 40 mole % TMCD, 20 to 30 mole % CHDM and 30 to 60 mole % ethylene glycol; and 20 to 40 mole % TMCD, 20 to 25 mole % CHDM and 30 to 60 mole % ethylene glycol.

In other aspects of the invention, the glycol component for the copolyesters (2) useful in the invention include but are not limited to at least one of the following combinations of ranges: 20 to 40 mole % TMCD, 25 to 40 mole % CHDM and 30 to 55 mole % ethylene glycol; 20 to 40 mole % TMCD, 25 to 35 mole % CHDM and 30 to 55 mole % ethylene glycol; and 20 to 40 mole % TMCD, 25 to 30 mole % CHDM and 30 to 55 mole % ethylene glycol.

In other aspects of the invention, the glycol component for the copolyesters (2) useful in the invention include but are not limited to at least one of the following combinations of ranges: 20 to 40 mole % TMCD, 30 to 40 mole % CHDM and 30 to 50 mole % ethylene glycol; 20 to 40 mole % TMCD, 30 to 35 mole % CHDM and 30 to 50 mole % ethylene glycol.

In one embodiment, the glycol component of the copolyesters (2) useful in the invention comprises TMCD and CHDM wherein the sum of the mole percentages of TMCD and CHDM is from 40 to less than 70 mole % of the total mole % of the total glycol component.

In certain embodiments, terephthalic acid or an ester thereof, such as, for example, dimethyl terephthalate or a mixture of terephthalic acid residues and an ester thereof can make up a portion or all of the dicarboxylic acid component used to form the polyesters useful in the invention. In certain embodiments, terephthalic acid residues can make up a portion or all of the dicarboxylic acid component used to form the polyesters useful in the invention. In certain embodiments, higher amounts of terephthalic acid can be used in order to produce a higher impact strength polyester. For purposes of this disclosure, the terms “terephthalic acid” and “dimethyl terephthalate” are used interchangeably herein. In one embodiment, dimethyl terephthalate is part or all of the dicarboxylic acid component used to make the polyesters useful in the polyer blends of the invention. In all embodiments, ranges of from 70 to 100 mole %; or 80 to 100 mole %; or 90 to 100 mole %; or 99 to 100 mole %; or 100 mole % terephthalic acid and/or dimethyl terephthalate and/or mixtures thereof may be used.

In addition to terephthalic acid, the dicarboxylic acid component of the copolyesters (1) and (2) useful in the polymer blends of the invention can comprise up to 30 mole %, up to 20 mole %, up to 10 mole %, up to 5 mole %, or up to 1 mole % of one or more modifying aromatic dicarboxylic acids. Yet another embodiment contains 0 mole % modifying aromatic dicarboxylic acids. Thus, if present, it is contemplated that the amount of one or more modifying aromatic dicarboxylic acids can range from any of these preceding endpoint values including, for example, from 0.01 to 30 mole %, 0.01 to 20 mole %, from 0.01 to 10 mole %, from 0.01 to 5 mole % and from 0.01 to 1 mole %. In one embodiment, modifying aromatic dicarboxylic acids that may be used in the present invention include but are not limited to those having up to 20 carbon atoms, and which can be linear, para-oriented, or symmetrical. Examples of modifying aromatic dicarboxylic acids which may be used in this invention include, but are not limited to, isophthalic acid, 4,4′-biphenyldicarboxylic acid, 1,4-, 1,5-, 2,6-, 2,7-naphthalenedicarboxylic acid, and trans-4,4′-stilbenedicarboxylic acid, and esters thereof. In one embodiment, the modifying aromatic dicarboxylic acid is isophthalic acid.

The carboxylic acid component of the copolyesters (1) and (2) useful in the polymer blends of the invention can be further modified with up to 10 mole %, such as up to 5 mole % or up to 1 mole % of one or more aliphatic dicarboxylic acids containing 2-16 carbon atoms, such as, for example, cyclohexanedicarboxylic, malonic, succinic, glutaric, adipic, pimelic, suberic, azelaic and dodecanedioic dicarboxylic acids. Certain embodiments can also comprise 0.01 to 10 mole %, such as 0.1 to 10 mole %, 1 or 10 mole %, 5 to 10 mole % of one or more modifying aliphatic dicarboxylic acids. Yet another embodiment contains 0 mole % modifying aliphatic dicarboxylic acids. The total mole % of the dicarboxylic acid component is 100 mole %. In one embodiment, adipic acid and/or glutaric acid are provided in the modifying aliphatic dicarboxylic acid component of the invention.

Esters of terephthalic acid and the other modifying dicarboxylic acids or their corresponding esters and/or salts may be used instead of the dicarboxylic acids. Suitable examples of dicarboxylic acid esters include, but are not limited to, the dimethyl, diethyl, dipropyl, diisopropyl, dibutyl, and diphenyl esters. In one embodiment, the esters are chosen from at least one of the following: methyl, ethyl, propyl, isopropyl, and phenyl esters.

The copolyesters (1) and (2) useful in the invention in general may be prepared by condensing the dicarboxylic acid or dicarboxylic acid ester with the glycol in the presence of the tin catalyst described herein at elevated temperatures increased gradually during the course of the condensation up to a temperature of about 225°-310° C., in an inert atmosphere, and conducting the condensation at low pressure during the latter part of the condensation, as described in further detail in U.S. Pat. No. 2,720,507 incorporated herein by reference.

The polymer blends of the present invention may include any various additives conventional in the art. For example, the polymer blend can include from about 0.01 to about 50 weight percent, based on the total weight of the composition, of at least one additional additive selected from a lubricant, a non-polymeric plasticizer, a thermal stabilizer, an antioxidant, a pro-oxidant, an acid scavenger, an ultraviolet light stabilizer, a promoter of photodegradation, an antistatic agent, a pigment, a dye, or a colorant. Typical non-polymeric plasticizers include dioctyl adipate, phosphates, and diethyl phthalate. Representative inorganics include, talc, TiO2, CaCO3, NH4CL, and silica. Colorants can be monomeric, oligomeric, and polymeric. Preferred polymeric colorants are aliphatic polyesters, aliphatic-aromatic copolyesters, or aromatic polyesters in which the color producing monomer, i.e., a dye, is covalently incorporated into the polymer. Such representative polymeric colorants are described by Weaver et al. in U.S. Pat. Nos. 4,892,922, 4,892,923, 4,882,412, 4,845,188, 4,826,903 and 4,749,773 the entire disclosures of which are incorporated herein by reference.

Although not essential, the polymer blends of the invention may comprise a plasticizer.

Examples of plasticizers which may be used according to the invention are esters comprising: (i) acid residues comprising one or more residues of: phthalic acid, adipic acid, trimellitic acid, benzoic acid, azelaic acid, terephthalic acid, isophthalic acid, butyric acid, glutaric acid, citric acid or phosphoric acid; and (ii) alcohol residues comprising one or more residues of an aliphatic, cycloaliphatic, or aromatic alcohol containing up to about 20 carbon atoms. Further, non-limiting examples of alcohol residues of the plasticizer include methanol, ethanol, propanol, isopropanol, butanol, isobutanol, stearyl alcohol, lauryl alcohol, phenol, benzyl alcohol, hydroquinone, catechol, resorcinol, ethylene glycol, neopentyl glycol, CHDM, and diethylene glycol. The plasticizer also may comprise one or more benzoates, phthalates, phosphates, or isophthalates. In another example, the plasticizer comprises diethylene glycol dibenzoate, abbreviated herein as “DEGDB”.

A flame retardant may be added to the polymer blend at a concentration of about 5 weight percent to about 40 weight percent based on the total weight of the polymer blend. Other examples of flame retardant levels are about 7 weight percent to about 35 weight percent, about 10 weight percent to about 30 weight percent, and about 10 weight percent to about 25 weight percent. Preferably, the flame retardant comprises one or more monoesters, diesters, or triesters of phosphoric acid. The phosphorus-containing flame retardant may also function as a plasticizer for the polyester. In another example, the plasticizer comprises diethylene glycol dibenzoate and the flame retardant comprises resorcinol bis(diphenyl phosphate). The flame retardant film or sheet will typically give a V2 or greater rating in a UL94 burn test. In addition, our flame retardant film or sheet typically gives a burn rate of 0 in the Federal Motor Vehicle Safety Standard 302 (typically referred to as FMVSS 302).

The phosphorus-containing flame retardant is preferably miscible with the polyester or the plasticized polyester. The term “miscible”, as used herein,” is understood to mean that the flame retardant and the plasticized polyester will mix together to form a stable mixture which will not separate into multiple phases under processing conditions or conditions of use. Thus, the term “miscible” is intended include both “soluble” mixtures, in which flame retardant and plasticized polyester form a true solution, and “compatible” mixtures, meaning that the mixture of flame retardant and plasticized polyester do not necessarily form a true solution but only a stable blend. Preferably, the phosphorus-containing compound is a non-halogenated, organic compound such as, for example, a phosphorus acid ester containing organic substituents. The flame retardant may comprise a wide range of phosphorus compounds well-known in the art such as, for example, phosphines, phosphites, phosphinites, phosphonites, phosphinates, phosphonates, phosphine oxides, and phosphates. Examples of phosphorus-containing flame retardants include tributyl phosphate, triethyl phosphate, tri-butoxyethyl phosphate, t-Butylphenyl diphenyl phosphate, 2-ethylhexyl diphenyl phosphate, ethyl dimethyl phosphate, isodecyl diphenyl phosphate, trilauryl phosphate, triphenyl phosphate, tricresyl phosphate, trixylenyl phosphate, t-butylphenyl diphenylphosphate, resorcinol bis(diphenyl phosphate), tribenzyl phosphate, phenyl ethyl phosphate, trimethyl thionophosphate, phenyl ethyl thionophosphate, dimethyl methylphosphonate, diethyl methylphosphonate, diethyl pentylphosphonate, dilauryl methylphosphonate, diphenyl methylphosphonate, dibenzyl methylphosphonate, diphenyl cresylphosphonate, dimethyl cresylphosphonate, dimethyl methylthiono-phosphonate, phenyl diphenylphosphinate, benzyl diphenylphosphinate, methyl diphenylphosphinate, trimethyl phosphine oxide, triphenyl phosphine oxide, tribenzyl phosphine oxide, 4-methyl diphenyl phosphine oxide, triethyl phosphite, tributyl phosphite, trilauryl phosphite, triphenyl phosphite, tribenzyl phosphite, phenyl diethyl phosphite, phenyl dimethyl phosphite, benzyl dimethyl phosphite, dimethyl methylphosphonite, diethyl pentylphosphonite, diphenyl methylphosphonite, dibenzyl methylphosphonite, dimethyl cresylphosphonite, methyl dimethylphosphinite, methyl diethylphosphinite, phenyl diphenylphosphinite, methyl diphenylphosphinite, benzyl diphenylphosphinite, triphenyl phosphine, tribenzyl phosphine, and methyl diphenyl phosphine.

The term “phosphorus acid” as used in describing the phosphorus-containing flame retardants of the invention include the mineral acids such as phosphoric acid, acids having direct carbon-to-phosphorus bonds such as the phosphonic and phosphinic acids, and partially esterified phosphorus acids which contain at least one remaining unesterified acid group such as the first and second degree esters of phosphoric acid and the like. Typical phosphorus acids that can be employed in the present invention include, but are not limited to: dibenzyl phosphoric acid, dibutyl phosphoric acid, di(2-ethylhexyl)phosphoric acid, diphenyl phosphoric acid, methyl phenyl phosphoric acid, phenyl benzyl phosphoric acid, hexylphosphonic acid, phenylphosphonic acid tolylphosphonic acid, benzyl phosphonic acid, 2-phenylethylphosphonic acid, methylhexylphosphinic acid, diphenylphosphinic acid, phenylnaphthylphosphinic acid, dibenzylphosphinic acid, methylphenylphosphinic acid, phenylphosphonous acid, tolylphosphonous acid, benzylphosphonous acid, butyl phosphoric acid, 2-ethyl hexyl phosphoric acid, phenyl phosphoric acid, cresyl phosphoric acid, benzyl phosphoric acid, phenyl phosphorous acid, cresyl phosphorous acid, benzyl phosphorous acid, diphenyl phosphorous acid, phenyl benzyl phosphorous acid, dibenzyl phosphorous acid, methyl phenyl phosphorous acid, phenyl phenylphosphonic acid, tolyl methylphos-phonic acid, ethyl benzylphosphonic acid, methyl ethylphosphonous acid, methyl phenylphosphonous acid, and phenyl phenylphosphonous acid. The flame retardant typically comprises one or more monoesters, diesters, or triesters of phosphoric acid. In another example, the flame retardant comprises resorcinol bis(diphenyl phosphate), abbreviated herein as “RDP”.

Oxidative stabilizers also may be used with polyesters of the present invention to prevent oxidative degradation during processing of the molten or semi-molten material on the rolls. Such stabilizers include esters such as distearyl thiodipropionate or dilauryl thiodipropionate; phenolic stabilizers such as IRGANOX® 1010 available from Ciba-Geigy AG, ETHANOX® 330 available from Ethyl Corporation, and butylated hydroxytoluene; and phosphorus containing stabilizers such as Irgafos® available from Ciba-Geigy AG and WESTON® stabilizers available from GE Specialty Chemicals. These stabilizers may be used alone or in combinations

The various components of the polymer blends such as, for example, the flame retardant, release additive, plasticizer, and toners, may be blended in batch, semicontinuous, or continuous processes. Small scale batches may be readily prepared in any high-intensity mixing devices well-known to those skilled in the art, such as Banbury mixers, batch mixers, ribbon blenders, roll mill, torque rheometer, a single screw extruder, or a twin screw extruder. The components also may be blended in solution in an appropriate solvent. The melt blending method includes blending the polyester, plasticizer, flame retardant, additive, and any additional non-polymerized components at a temperature sufficient to melt the polyester. The blend may be cooled and pelletized for further use or the melt blend can be calendered directly from this molten blend into film or sheet. The term “melt” as used herein includes, but is not limited to, merely softening the polyester. For melt mixing methods generally known in the polymer art, see “Mixing and Compounding of Polymers” (I. Manas-Zloczower & Z. Tadmor editors, Carl Hanser Verlag Publisher, 1994, New York, N.Y.). When colored sheet or film is desired, pigments or colorants may be included in the polyester mixture during the reaction of the diol and the dicarboxylic acid or they may be melt blended with the preformed polyester. A preferred method of including colorants is to use a colorant having thermally stable organic colored compounds having reactive groups such that the colorant is copolymerized and incorporated into the polyester to improve its hue. For example, colorants such as dyes possessing reactive hydroxyl and/or carboxyl groups, including, but not limited to, blue and red substituted anthraquinones, may be copolymerized into the polymer chain. When dyes are employed as colorants, they may be added to the polyester reaction process after an ester interchange or direct esterification reaction.

The polymer blends of the present invention are characterized by a novel combination of properties which preferably include polymer blends having a clearness or clarity determined by visual observation, or haze value measured on ⅛ inch (3.2 mm) molded samples of about 0.2 to 3.0 percent as determined by a HunterLab UltraScan Sphere 8000 using Hunter's Universal Software, where % Haze=100*DiffuseTransmission/TotalTransmission. Diffuse transmission is obtained by placing a light trap on the other side of the integrating sphere from where the sample port is, thus eliminating the straight-thru light path. Only light scattered by greater than 2.5 degrees is measured. Total transmission includes measurement of light passing straight-through the sample and also off-axis light scattered to the sensor by the sample. The sample is placed at the exit port of the sphere so that off-axis light from the full sphere interior is available for scattering. Regular transmission is the name given to measurement of only the straight-through rays—the sample is placed immediately in front of the sensor, which is approximately 20 cm away from the sphere exit port—this keeps off-axis light from impinging on the sample. The polymer blends also exhibit an ASTM D648 a Heat Deflection Temperature, at 455 kilopascals bar (kPa—66 pounds per square inch—psi), of about 80 to 130° C., an ASTM D256 Notched Izod Impact Strength Flexural at 23° C. of about 50 to 1250 joules/m (1 to 25 foot-pounds/inch), an ASTM D790 Modulus of about 700 to 3500 kPa (100 to 500 psi), an ASTM D790 Flexural Strength of about 5000 to 15000 psi. The tensile properties of the blend determined according to ASTM D638 at 23° C. comprise a yield stress of about 31 to 69 megapascal (Mpa—about 4500 psi to 10000 psi), a break stress of about 31 to 69 MPa (about 4500 psi to 10000 psi), and a break strain of at least 50%.

The polyester blend may also be formed into film or sheet using many methods known to those skilled in the art, including but not limited to extrusion and calendaring. In the extrusion process, the polyesters, typically in pellet form, are mixed together in a tumbler and then placed in a hopper of an extruder for melt compounding. Alternatively, the pellets may be added to the hopper of an extruder by various feeders, which meter the pellets in their desired weight ratios. Upon exiting the extruder the now homogenous copolyester blend is shaped into a film. The shape of the film is not restricted in any way. For example, it may be a flat sheet or a tube. The film obtained may be stretched, for example, in a certain direction by from 2 to 6 times the original measurements.

In a general embodiment, the polymer blends of the invention are useful in making calendared film and/or sheet on calendaring rolls. The polymer blend may also comprise one or more additives to increase the flexibility and softness of calendared polyester film, improve the processing of the polyester, and help to prevent sticking of the polyester to the calender rolls. The invention also provides a process for film or sheet by calendering the novel polymer blends and for the film or sheet produced from such calendering processes. The calendered film or sheet typically have a thickness in the range of about 2 mils (0.05 mm) to about 80 mils (2 mm).

While the inherent viscosity (I.V.) of the polyesters of the present invention is generally from about 0.4 to about 1.4 dL/g, other I.V.s are contemplated within the scope of this invention. The inherent viscosity, abbreviated herein as “I.V.”, refers to inherent viscosity determinations made at 25° C. using 0.25 gram of polymer per 50 mL of a solvent composed of 60 weight percent phenol and 40 weight percent tetrachloroethane. The basic method of determining the I.V. of the polyesters herein is set forth in ASTM method D2857-95. To obtain superior calendering line speeds, the polyesters of the present invention preferably have an inherent viscosity of about 0.55 to about 0.75 dL/g. Other examples of I.V. values which may be exhibited by the polymer blends are about 0.55 to about 0.70 dL/g, about 0.55 to about 0.65 dL/g, and about 0.60 to about 0.65 dL/g.

In addition to the polyester, the polymer blends described above may comprise an additive that is effective to prevent sticking of the polyester to the calendering rolls when the polyester is used to make calendered film. Examples of these particular additives of the present invention include fatty acid amides such as erucylamide and stearamide; metal salts of organic acids such as calcium stearate and zinc stearate; fatty acids such as stearic acid, oleic acid, and palmitic acid; fatty acid salts; fatty acid esters; hydrocarbon waxes such as paraffin wax, phosphoric acid esters, polyethylene waxes, and polypropylene waxes; chemically modified polyolefin waxes; ester waxes such as carnauba wax; glycerin esters such as glycerol mono- and di-stearates; talc; microcrystalline silica; and acrylic copolymers (for example, PARALOID® K175 available from Rohm & Haas). Typically, the additive comprises one or more of: erucylamide, stearamide, calcium stearate, zinc stearate, stearic acid, montanic acid, montanic acid esters, montanic acid salts, oleic acid, palmitic acid, paraffin wax, polyethylene waxes, polypropylene waxes, carnauba wax, glycerol monostearate, or glycerol distearate.

Another additive which may be used comprises a fatty acid or a salt of a fatty acid containing more than 18 carbon atoms and (ii) an ester wax comprising a fatty acid residue containing more than 18 carbon atoms and an alcohol residue containing from 2 to about 28 carbon atoms. The ratio of the fatty acid or salt of a fatty acid to the ester wax may be 1:1 or greater. In this embodiment, the combination of the fatty acid or fatty acid salt and an ester wax at the above ratio gives the additional benefit of providing a film or sheet with a haze value of less than 5%. The additives with fatty acid components containing 18 or less carbon atoms

In addition to the polyester, the polymer blends described above may comprise an additive that is effective to prevent sticking of the polyester to the calendering rolls when the polyester is used to make calendered film. As used herein, the term “effective” means that the polyester passes freely between the calendering rolls without wrapping itself around the rolls or producing an excessive layer of polyester on the surface of the rolls. The amount of additive used in the polyester resin composition is typically about 0.1 to about 10 weight percent, based on the total weight percent of the polymer blend. The optimum amount of additive used is determined by factors well known in the art and is dependent upon variations in equipment, material, process conditions, and film thickness. Additional examples of additive levels are about 0.1 to about 5 weight percent and about 0.1 to about 2 weight percent. Examples of additives of the present invention include fatty acid amides such as erucylamide and stearamide; metal salts of organic acids such as calcium stearate and zinc stearate; fatty acids such as stearic acid, oleic acid, and palmitic acid; fatty acid salts; fatty acid esters; hydrocarbon waxes such as paraffin wax, phosphoric acid esters, polyethylene waxes, and polypropylene waxes; chemically modified polyolefin waxes; ester waxes such as carnauba wax; glycerin esters such as glycerol mono- and di-stearates; talc; microcrystalline silica; and acrylic copolymers (for example, PARALOID® K175 available from Rohm & Haas). Typically, the additive comprises one or more of: erucylamide, stearamide, calcium stearate, zinc stearate, stearic acid, montanic acid, montanic acid esters, montanic acid salts, oleic acid, palmitic acid, paraffin wax, polyethylene waxes, polypropylene waxes, carnauba wax, glycerol monostearate, or glycerol distearate.

Another additive which may be used comprises a fatty acid or a salt of a fatty acid containing more than 18 carbon atoms and (ii) an ester wax comprising a fatty acid residue containing more than 18 carbon atoms and an alcohol residue containing from 2 to about 28 carbon atoms. The ratio of the fatty acid or salt of a fatty acid to the ester wax may be 1:1 or greater. In this embodiment, the combination of the fatty acid or fatty acid salt and an ester wax at the above ratio gives the additional benefit of providing a film or sheet with a haze value of less than 5%. The additives with fatty acid components containing 18 or less carbon atoms In addition to the polyester, the polymer blends described above may comprise an additive that is effective to prevent sticking of the polyester to the calendering rolls when the polyester is used to make calendered film. As used herein, the term “effective” means that the polyester passes freely between the calendering rolls without wrapping itself around the rolls or producing an excessive layer of polyester on the surface of the rolls. The amount of additive used in the polyester resin composition is typically about 0.1 to about 10 weight percent, based on the total weight percent of the polymer blend. The optimum amount of additive used is determined by factors well known in the art and is dependent upon variations in equipment, material, process conditions, and film thickness. Additional examples of additive levels are about 0.1 to about 5 weight percent and about 0.1 to about 2 weight percent. Examples of additives of the present invention include fatty acid amides such as erucylamide and stearamide; metal salts of organic acids such as calcium stearate and zinc stearate; fatty acids such as stearic acid, oleic acid, and palmitic acid; fatty acid salts; fatty acid esters; hydrocarbon waxes such as paraffin wax, phosphoric acid esters, polyethylene waxes, and polypropylene waxes; chemically modified polyolefin waxes; ester waxes such as carnauba wax; glycerin esters such as glycerol mono- and di-stearates; talc; microcrystalline silica; and acrylic copolymers (for example, PARALOID® K175 available from Rohm & Haas). Typically, the additive comprises one or more of: erucylamide, stearamide, calcium stearate, zinc stearate, stearic acid, montanic acid, montanic acid esters, montanic acid salts, oleic acid, palmitic acid, paraffin wax, polyethylene waxes, polypropylene waxes, carnauba wax, glycerol monostearate, or glycerol distearate.

Another additive which may be used comprises a fatty acid or a salt of a fatty acid containing more than 18 carbon atoms and (ii) an ester wax comprising a fatty acid residue containing more than 18 carbon atoms and an alcohol residue containing from 2 to about 28 carbon atoms. The ratio of the fatty acid or salt of a fatty acid to the ester wax may be 1:1 or greater. In this embodiment, the combination of the fatty acid or fatty acid salt and an ester wax at the above ratio gives the additional benefit of providing a film or sheet with a haze value of less than 5%. The additives with fatty acid components containing 18 or less carbon atoms which all the reactants are added at the beginning of the process except that one or more of the products are removed continuously as the reaction progresses. The process is operated advantageously as a continuous process for economic reasons and to produce superior coloration of the polymer as the polyester may deteriorate in appearance if allowed to reside in a reactor at an elevated temperature for too long a duration.

In the calendaring process, higher molecular weight plasticizers are preferred to prevent smoking and loss of plasticizer during the calendering process. The preferred range of plasticizer content will depend on the properties of the base polyester and the plasticizer. In particular, as the Tg of the polyester as predicted by the well-known Fox equation (T. G. Fox, Bull. Am. Phys. Soc., 1, 123 (1956)) decreases, the amount of plasticizer needed to obtain a polymer blend that may be calendered satisfactorily also decreases. Typically, the plasticizer comprises from about 5 to about 50 weight percent (weight percent) of the polymer blend based on the total weight of the polymer blend. Other examples of plasticizer levels are about 10 to about 40 weight percent, about 15 to about 40 weight percent, and about 15 to about 30 weight percent of the polymer blend.

Our invention also includes a process for the manufacture of film or sheet, comprising any of the polymer blends of the invention. In some embodiments, a process is disclosed for making such articles, film, sheet, and/or fibers comprising the steps of injection molding, extrusion blow molding, film/sheet extruding or calendering the polymer blend(s) of the invention.

The present invention is illustrated in greater detail by the specific examples presented below. It is to be understood that these examples are illustrative embodiments and are not intended to be limiting of the invention, but rather are to be construed broadly within the scope and content of the appended claims.

Examples

The invention is further illustrated by the following examples. The inherent viscosity of the polyesters was determined in 60/40 (wt/wt) phenol/tetrachloroethane at a concentration of 0.5 g/100 ml at 25° C. according to standard methods that are described in ASTM Method D4603. The glass transition temperatures were determined using a Perkin Elmer differential scanning calorimeter (DSC) at a scan rate of 20° C. The composition of the neat resins was determined by proton nuclear magnetic resonance spectroscopy (NMR). Clarity was determined by visual inspection. The miscibility of the blends was determined by the presence of a single glass transition and clarity of the blended resin exiting the extruder after cooling.

In one embodiment, this invention includes articles of manufacture comprising any of the polyester blends of the invention.

The invention further relates to the film(s) and/or sheet(s) comprising the polyester blends. The methods of forming the polyesters into film(s) and/or sheet(s) are well known in the art. Examples of film(s) and/or sheet(s) of the invention including but not limited to extruded film(s) and/or sheet(s), calendered film(s) and/or sheet(s), compression molded film(s) and/or sheet(s), solution casted film(s) and/or sheet(s). Methods of making film and/or sheet include but are not limited to extrusion, calendering, compression molding, and solution casting. In one embodiment, this invention includes articles of manufacture comprising the polyester blends of the invention.

In one embodiment, this invention includes articles of manufacture comprising any of the polyester blends of the invention which is extrusion molded.

In one embodiment, this invention includes articles of manufacture comprising any of the polyester blends of the invention which is extrusion stretch blow molded.

In one embodiment, this invention includes articles of manufacture comprising any of the polyester blends of the invention which is injection molded.

In one embodiment, this invention includes articles of manufacture comprising the polyester blends of the invention which is injection blow molded.

In one embodiment, this invention includes articles of manufacture comprising the polyester blends of the invention which is injection stretch blow molded.

In one embodiment, the articles of manufacture included in this invention are visually clear comprising any of the polyester blends of the invention.

Examples of potential articles made from the polymer blends useful in the invention include, but are not limited, to uniaxially stretched film, biaxially stretched film, shrink film (whether or not uniaxially or biaxially stretched), liquid crystal display film (including, but not limited to, diffuser sheets, compensation films, brightness enhancing films, and protective films), thermoformed sheet, graphic arts film, outdoor signs, skylights, coating(s), coated articles, painted articles, laminates, laminated articles, and/or multiwall films or sheets.

Material Descriptions

Copolyesters (1) and (2) used in the present invention are described in Table 1 below, along with suitable nomenclature; additionally the Tg as measured by DSC for the neat copolyesters (1) and (2) are provided.

Additional details can be found regarding the synthesis and characterization of these NPG and TMCD containing resins, see U.S. Patent Application 2006-0100393A1 and U.S. Patent Application 2010-0099828 respectively. In general typical IV ranges for these NPG containing copolyesters range from 0.7 to 0.77, and for the TMCD containing copolyesters from 0.59 to 0.66.

TABLE 1 Neat copolyesters used for blend preparation Co- polyester Number DSC 1^(st) DSC Code heat 2^(nd) heat Polyester mole % of species as diacid or diol (° C.) (° C.) Number T I NPG TMCD CHDM EG Tg Tg 1 100 0 0 23 77 0 112 111 2 100 0 0 33 67 0 117 115 3 100 0 0 44 56 0 128 126 4 100 0 100 0 0 0 78 75 5 100 0 77 0 23 0 79 78 6 100 0 55 0 45 0 82 83 7 100 0 47 0 53 0 84 84 8 100 0 79 0 21 0 86 89 9 74 26 0 0 100 0 86 88 10 100 0 33 0 0 67 77 78

Blend Preparation

The copolyesters (1) and (2) were dried overnight in a desiccant forced air oven from 70 to 90° C., depending on the resin Tg. The copolyester components were premixed by bag blending and then fed to a 19 mm APV twin screw extruder equipped with a moderate mixing-distributing screw design. The extruder was set at 250° C. at the feed zone and at 275° C. at the remaining 4 zones. All blends compounded at a screw RPM of 300 under similar thermal profiles. Observations regarding clarity were made as the polymer melt was exiting the die, as a strand from the die was quickly quenched in chilled water, and some polymer melt was collected on a room temperature surface and allowed to slowly cool. Table 2 shows the resulting observations of the most rigorous test of miscibility, the slow-cooled sample. Examples 1 to 3 have some haze, indicating that a definitive level of CHDM is required for miscibility between these systems. Lower haze is observed in examples 3 to 14. As a comparative example, blends were prepared that show the combination of NPG with CHDM is more a necessity than just the presence of NPG. Examples 15 to 16 are blends with EG/NPG copolyesters with TMCD/CHDM copolyersters. These blends had significant haze and were virtually opaque.

TABLE 2 Blend Examples and Haze observation Sample ID Copolyester 1 - Copolyester 2 - See Table 1 Number See Table 1 Number Haze level code for code for Low, some, Example Compositions Compositions or high 1 1 4 Some 2 3 4 Some 3 1 5 Low to some 4 2 5 Low to some 5 3 5 Low 6 1 6 Low 7 3 6 Low 8 1 7 Low 9 2 7 Low 10 1 8 Low 11 2 8 Low 12 1 9 Low 13 2 9 Low 14 3 9 Low 15 1 10 High 16 2 10 High 17 3 10 High

Lastly, DSC was performed on samples of quenched strand. Both the first and second heats were documented as shown in Table 3 along with the Tg of the neat component (2) copolyesters. It is clear that the minimum amount of CHDM in Copolyester 2 required for miscibility is about 20% in this NPG/CHDM-TMCD/CHDM system.

TABLE 3 DSC Results from blends shown in Table 2 Sample ID Copolyester 1 - Copolyester 2 - Tg (° C.) of Tg (° C.) of See Table 1 See Table 1 each each Number code Number code Copolyester Copolyester 1^(st) heat 2^(nd) heat Miscible for for (1) by DSC (2) by DSC (° C.) (° C.) Yes, no, Example Compositions Compositions 2^(nd) Heat Heat Tg₁ Tg₂ Tg₁ Tg₂ partial 1 1 4 111 75 78 102 80 95 No 2 3 4 126 75 79 112 81 102 No 3 1 5 111 78 56 92 88 Yes-partial 4 2 5 115 78 86 82 96 Yes-partial 5 3 5 126 78 89 90 Yes 6 1 6 111 83 97 92 Yes 7 3 6 115 83 102 97 Yes 8 1 7 111 84 103 93 Yes 9 3 7 126 84 88 102 98 Yes 10 1 8 111 89 101 97 Yes 11 3 8 126 89 107 103 Yes 12 1 9 111 88 95 95 Yes 13 2 9 115 88 99 98 Yes 14 3 9 126 88 100 101 Yes 15 1 10 111 78 75 108 78 104 No 16 2 10 115 78 71 114 78 110 No 17 3 10 126 78 75 124 78 119 No

The invention has been described in detail with particular reference to preferred embodiments thereof, but it will be understood that variations and modifications can be effected within the spirit and scope of the invention. 

1. A miscible blend comprising: (A) 1 to 99 percent by weight of a first copolyester comprising: (i) diacid residues comprising about 65 to 100 mole percent of dicarboxylic acid residues selected from the group consisting of terephthalic acid residues, isophthalic acid residues, or mixtures thereof; about 0 to 35 mole percent of modifying diacid residues having from about 2 to 20 carbon atoms, wherein the total mole percent of diacid residues is equal to 100 mole percent; and (ii) diol residues comprising about 1 to 100 mole percent 1,4-cyclohexanedimethanol residues, and about 99 to 0 mole percent diol residues selected from the group consisting of 2,2-dimethyl-1,3-propanediol, ethylene glycol and 1,4-cyclohexanedimethanol; wherein the total mole percent of diol residues is equal to 100 mole percent; and (B) 1 to 99 percent by weight of a second copolyester comprising: (i) diacid residues comprising about 65 to 100 mole percent of dicarboxylic acid residues selected from the group consisting of terephthalic acid residues, isophthalic acid residues, or mixtures thereof; and about 0 to 35 mole percent of modifying diacid residues having from about 2 to 20 carbon atoms, wherein the total mole percent of diacid residues is equal to 100 mole percent; and, (ii) diol residues comprising about 1 to 99 mole percent 1,4-cyclohexanedimethanol residues and about 99 to 1 mole percent 2,2,4,4-tetramethyl-1,3-cyclobutanediol residues, wherein the total mole percent of diol residues is equal to 100 mole percent; wherein the total weight percent for the blend equals 100 weight percent.
 2. The blend of claim 1 wherein at least one of said first and second polyesters comprise about 0.05 to 1.0 mole percent of residues of a trifunctional monomer based on the total mole percentage of the diacid residues or diol residues.
 3. The blend of claim 1 wherein the blend comprises at least one additive.
 4. The blend of claim 1 wherein the second polyester comprises about 55 to 80 mole percent 1,4-cyclohexanedimethanol residues and about 20 to 45 mole percent 2,2,4,4-tetramethyl-1,3-cyclobutanediol residues.
 5. The blend of claim 1 or 4 wherein the first polyester comprises about 20 to 55 mole percent 1,4-cyclohexanedimethanol residues and about 45 to 80 mole percent neopentyl glycol residues.
 6. The blend of claim 1 wherein the first polyester comprises 100 mole % 1,4-cyclohexanedimethanol. 